I mainly play Aeon and build spreadsheets to analyse the fairness across units/factions. My opinions are only that, opinions, yet I shall when relevant or possible attempt to corroborate them with facts or figures. Now for my thoughts about your post @FunkOff . By the way, thank you for numbering your points.

1. Aurora dying to air is a weakness but their counteracting strength is their hover. This principle also holds true for Zthuee's as they hover and die to bombers in one shot. In regards to the Aurora speed, being slow is necessary otherwise (assuming perfect micro and unit control) the Aurora will kill all T1 + ACU without ever taking damage. I said all T1 full knowing T1 mobile artillery outranges the Aurora. Typically by microing forwards and backwards at the edge of the T1 mobile artillery range you can avoid their shots. I however understand as players performing that level of micro is hard and we often lose many Aurora to a few T1 mobile artillery. Each T1 mobile artillery has at minimum 45 damage per shot (Zthuee). Zthuee fires 5 shots. 3 hits will reduce Aurora to 135 hp. 4 shots will kill the Aurora with 40 overkill. Increasing Aurora HP by 15 will not solve the "problem". Medusa does 200 damage per shot. Aurora HP would need to be >200 to survive. I am mostly sure this level of HP increase is imbalanced.
2. Fervor is great at killing point defence or other structures and terrible against units. This is by design. Aeon are the best at doing one job, but try and make their units do anything other than that one job and they become the worst. Fervor has 22.4 more damage per second than the next most damaging T1 mobile artillery and this reflects the Aeon design philosophy nicely.
3. The Beacon frigate. I'm still analysing that unit so I'll forgo commenting on it except to say it has a very complex role in the Aeon navy as it is distinctly different from the other faction's frigates.
4. The shard. Currently has 45 muzzle velocity, the same as the Thistle and 15 greater than frigate anti air. Thinking simply, the shard is an overpriced water travelling Thistle that moves quicker. Both the Thistle and Shard are inferior (vastly) to air interceptors. If required I can post statistical proof later. If you want air cover, build interceptors as the other T1 alternatives can't compete. However if you are desperate you can build ground or naval anti air. Next is where it gets complicated. Assuming you are still reading at this point you may notice several things. Down the bottom is an example naval fleet consisting of 5 Beacon Class frigates, 2 Shards and 6 Thunderhead class frigates. The Aeon fleet is almost equal to the UEF fleet but has 1870 less HP but 5 anti-torpedo launchers. Is this balanced? Is having one less frigate worth 5 anti-torpedoes? You decide. Is the Shard balanced as part of navy? Yes. Is it useful? No. Should it hit more often? Yes because there are less of them compared to frigates and quality is required to counteract quantity.
5. Shimmer stun time is a point of potential imbalance. I shall now point out a myriad of different factors to consider when deciding if the Shimmer is indeed imbalanced. Shimmer stuns for 2 seconds. Medusa stuns for 3.5 seconds. These values were measured in-game not taken from the unit database. With stun duration, we have to factor in stun frequency and stun area. Medusa has 2 radius while Shimmer has 4. Medusa hits target every 6 seconds while Shimmer without micro (meaning without hover bomb) hits every 10 seconds. The Shimmer in the unit data has a fire cycle of 5 seconds but a flight path of 10 seconds, resulting in a 10 second fire cycle. Compounding this data the Medusa stuns for 1.75x longer, fires 1.67x faster and hits 0.25x more area (<-simple geometry). Assuming simple multiplication can deduce effectiveness, the Medusa is 0.73x more effective than the Shimmer at stunning if units can't die. But units die, thus reducing their effectiveness. HP per mass the Medusa is 2x more efficient, has 0.683x more HP and T1 interceptors deal 1.8x the damage of T1 tanks for 0.935x the mass cost on average. Additionally the Medusa costs 0.34x more mass and 0.0735x more energy. To calculate an adjusted effectiveness rating the standard effectiveness should be multiplied by survivability (HP ratio) and divided by cost (using mass ratio for simplicity's sake). This yields the formula: 1.75 x 1.67 x 0.25 x 0.683 / 0.34 = 1.467. At this point I expect the reader is drowning in values and simple calculations if they are still reading at all! To summarise, the Medusa is 1.467 times stronger at stunning stuff than the Shimmer. Perhaps the balance team could consider increasing the 2 second Shimmer stun too 2 x 1.467. Or 2.5 seconds!
6. Transports are a factional thing that are designed to give the faction uniqueness and compensate for general imbalance due to factional gimmicks.
7. The Aeon T3 bomber is imbalanced (weak). Here are the facts explaining why. Currently the ratio between damage and payload radius is: Damage = 4500-(Radius*250). I shall assume this ratio has been tested to be “balanced”. Each T3 bomber follows this rule except Aeon, why? Subsequent question. Why are the AA ‘goodies’ on the UEF T3 bomber stronger than the Cybran T3 bomber? If the answer is because Cybran has stealth, why don’t Aeon or Seraphim have AA? What ‘buff’ counteracts this imbalance? Next topic. Each T3 bomber has a different set of stats which makes them more or less suited to fulfilling a particular role. First a table indicating the relationship between Mass Extractors and T3 bombers. Next the radius for each bomber. Cybran=7, UEF=6, Seraphim=5, Aeon=4. The Aeon bomber is just as good at killing Mass Extractors as the Seraphim Bomber yet has 1 less radius. Imbalance. You may say “the Aeon bomber has more damage to compensate for this” and this is wrong. The Aeon bomber only has 200 not 250 extra damage over the Seraphim bomber and doesn’t follow the “balanced” ratio! Imbalance. Solution is to add 50 damage to the Aeon Bomber. Just do it.
   Now onto the goodies (T3 bomber anti-air). Seraphim and Aeon don’t have goodies like UEF (their anti-air) or Cybran (anti-air + Stealth). Aeon is the closest to Cybran with only 100 more hp. Does having 100 more HP justify no anti-air or Stealth? No. People may say “but Aeon deals a whopping 700 more damage” but they also forgot that it has 3 less radius. Remember we are assuming the ratio for radius too damage is correct, so clearly the Aeon bomber is underpowered (provided the ratio is balanced). Now for Seraphim. They have 200 more HP than Cybran and 100 less than UEF and STILL don’t have anti-air! How can you justify giving the UEF T3 bomber AA and not the Seraphim bomber! UEF favouritism I see… However if the Aeon T3 bomber was to get tracking on their bomb, I would expect the bomber price to increase drastically, or the tracking to be negligible/non-existent.
8. Ah, the Aeon T2 Shield Generator. I'll start by putting forth the premise that the most efficient/best shield will have the best shield density per mass ratio. To save my readers brain cells I'll just tell you what these ratios are, but you can work them out yourself. Side note: Shields are a factional distinction, just like building HP. I've also included the HP of the Shield structure into my calculations as technically it counts as damage absorption, which is the purpose of a shield. Best T2: Cybran > Aeon > UEF > Seraphim.
   Best T3: Aeon > Cybran > UEF > Seraphim.
   Additional side note: UEF T3 Shield Generator recharge time is faster than everything except Cybran ED1: T2 Shield Generator. Also the Seraphim have the largest+strongest shield, but least efficient.
9. Galactic Colossus. A reasonable unit with a software error in it's tractor claws. The Galactic Colossus tractor arm in-game only activates once per 12ish seconds when tested (GC idle against Percival’s moving towards it). In the unit data (https://github.com/FAForever/fa/blob/develop/units/UAL0401/UAL0401_unit.bp), each of the two claws is supposed to have a fire rate of 0.15shots/second which is about 6.6 seconds per activation per claw. Why the major discrepancy between what actually happens and what is supposed to happen? Conclusion, a software error. Can this please be fixed to make the Galactic Colossus more consistent?

Also, add an energy cost to the Satellite that increases as the Satellite gets further from its command centre.

Reason: Teleportation range has been nerfed with a variable energy cost and charge time depending on range. This was because unlimited and unrestricted range was too strong. The Novax Satellite having unlimited range is a similar problem.

Credit for the idea: https://forum.faforever.com/topic/7080/satellite-overperforming/44

Showcase the Problem, Part D. biass and Dragun101 created a thread on how to make a sim mod to showcase your solution in a real game.
https://forum.faforever.com/topic/739/guide-creating-a-basic-balance-mod-with-a-merge-blueprint

No one will admit it, but T1 mobile arty is the strongest unit in the game.

It is viable at all stages of the game because of its amazing range, low cost, high DPS and great alpha strike.
E.g. You lose your T3 land, so you spam T1 arty. They are cheaper than T1 tanks after all.
This works because people's APM is limited, but T1 arty is plentiful and only requires shooting once or twice to be effective.

My belief is that T1 arty should be used to counter T1 PD, be good at neutralising structures, and have VERY limited effectiveness at killing experimentals, or literally anything that CAN move. This is not the case in the present state of the game.

Normally at this point in my post, I'd post a bunch of statistics proving the point. However, historically everyone has ignored the mathematics and just said "skill issue". So, I'll save myself some time and not bother.

If anyone is inclined to believe T1 arty is over performing, despite my deliberate lack of supportive evidence, read on to my proposed change for T1 arty.

In order to make T1 arty better, it first needs to become worst at killing stuff which can move, while keeping its effectiveness at killing T1 PD and structures.
Also, each faction has a point of uniqueness to their T1 arty which I would like to emphasis more.

The first step to making T1 arty worse at killing units is to turn off predictive projectiles. This would mean that any moving unit is virtually unhittable.
Excellent; we solved one problem but made another. Now all T1 arty feels useless.
Not so fast! We can give it various boons/buffs that should only apply to its intended role (detailed later). But now you say it is too good at killing bases (there's no pleasing some people).
Alright, we'll double the cost of the unit, increase DPS by half, and give it a smidgen more range (+2) to make it easier to use. And we are done! We now have an effective T1 PD killing machine, that costs lots, is easy to kill if unprotected and can't shred higher tech units by accident.

Now we have to increase the faction diversity of each T1 arty.

For the UEF. It has a vision ability and massive alpha damage. These are traits we want to keep and accentuate. It also has too much move speed compared to other factions (cybran needs the speed. I'll explain later), so we'll reduce this (I can already feel the rage from 90% of players for this).
Just because people like numbers, here they are.
Cost: 2x
Range: +2
Predictive projectiles: No
RoF: Halved
DPS: Doubled (this is DPS, not damage per shot)
Vision ability area: Doubled.
Conclusion. A vision granting, hard hitting monster that can smash a PD in only a few shots before the enemy can push them away. Classic UEF battle tactics.

For the Cybran. Their T1 arty is fast, has good aoe, is terribly inaccurate and stuns. We'll keep these and accentuate them. It also has pathetic DPS. We'll keep and accentuate this too! The speed will be increased so it can keep up with the mantis on raids, stunning PD so the mantis can wreck house. But we will keep its DPS the same, even though the cost is doubled, so it really becomes a proper supportive tool. To make it actually useful, we'll also increase the stun duration by a lot, but it can only stun PD (only T1 and T2 PD, leaving T3 alone just for you, you pampered UEF players).
Just because people like numbers, here they are.
Cost: 2x
Range: +2
Predictive projectiles: No
Speed: Increased to 3.7 (same as mantis)
AOE: increased by half
Firing randomness: increased by a quarter.
RoF: Increased by half
DPS: Unchanged
Stun duration: 5 seconds (can't stack but can refresh)
Conclusion. A stun machine that allows cybran bugs to crawl into your base, but is virtually useless by itself.

For the Aeon. Their T1 arty is precise, fast firing, has the highest DPS, but no AOE and sucks at literally everything else. We will keep all of these traits except the fast firing aspect. It would be easy just to say they only get stat changes, because this would make balancing easy. But that's no fun.
Keeping in theme for the Aeon, we'll use the old graphic of the mercy projectiles and have the balls of light shot by the T1 arty break up into that above its target. This will guarantee perfect accuracy, but unlike the old mercy, these projectiles won't track their target.
Just because people like numbers, here they are.
Cost: 2x
Range: +2
Predictive projectiles: No
RoF: Increased by half
DPS: Doubled
AOE: zero
Accuracy: perfect
Conclusion. Assassinates PD like a boss, but cries if you missclick onto the walls around it!

For the Seraphim. Their T1 arty fires fast, has good AOE but isn't overly accurate. We will accentuate the fast firing nature as this is their defining quality. The Seraphim are also aliens so physics don't apply to them quite the same. For this reason we'll increase the rate of time applied to the projectile. This means the projectile will fly faster, but also be affected by gravity just as quickly. It will look like the projectile is being shown on a video at times two speed.
Just because people like numbers, here they are.
Cost: 2x
Range: +2
Predictive projectiles: No
RoF: Tripled
DPS: Doubled
Rate of time applied to projectile: Doubled
Conclusion. Because their projectiles fire and fly so obscenely fast compared to the other factions, they have a very slim chance of actually hitting a moving unit if it retraces its steps. Otherwise, it is not special and has only received the universal changes to all T1 arty.

Wow. You made it to the end! Congratulations. Bake yourself a cake, you deserve it.

That mod idea about not having move commands get converted into a patrol, can that be made please! I'd 100% use that mod always.

Long way back to opening post. Glad to see you are championing FAF in a positive way. It is good to see someone address the toxicity issue as it has gotten rather bad because of some bad apples (I won't name names).
One of my FAF friends got traumatized from 1v1 toxicity so I had to make a mod to destroy chat so he could feel comfortable playing again. This is just in game and not on the message boards.
This forum post left a bad taste in my mouth yet I hope for a positive outcome.
Disclaimers: 1. I just want my friend to feel comfortable playing socially again. 2. I don't care about politics.

I would like to see the T2 PD for Aeon get an AOE buff. It's tragic how the animation and AOE do not match. Its overkill is so terrible, a little buff to AOE might mitigate this "feels bad" aspect of the structure.
Also increasing the projectile AOE on the T2 destroyer for Aeon might be a good idea, but it would need monitoring.

@FunkOff I systematically disagree with almost every single point you made in your original post.

1. T1 UEF tank. Highest HP, lowest DPS, slightly below average speed, highest cost, 1 rank vet adds extra acu shot to kill, etc... Lots of differences between the T1 tanks. However when used the sum total of their differences balance out resulting in no faction having a distinct advantage. E.g. yes the striker may be very very very slightly inferior to other t1 tanks, but UEF T1 factory has 500+ more hp for no additional cost making t1 arty take longer to kill it. Little things like this make the T1 phase balanced.
2. T1 UEF bomber has a different play style to a basic bomber (like the Sinnve). Just use it in a way that capitalises on it's AOE plus high damage. If units dodge it reliably, rejoice because you know the enemy is burning APM which you aren't.
3. T2 UEF static arty is the second cheapest, not most expensive. T2 UEF PD is most expensive but the best all rounder, with highest HP, second lowest DPS, tied best AOE, good high fire arc and quick fire cycle. This makes it the best all rounder T2 PD in the game. If you desire a more specialised PD, play another faction. Aeon for alpha damage + slow fire cycle, cybran for cheap fast lazers and seraphim for... honestly not sure.
4. Rhino never kill mongoose if mongoose are microed. They have too much range and speed. Pillars cost 68% of the mass of a Rhino so they obviously lose 1v1. FtXCommando also illustrated what advantages Pillars have over Rhino.
5. Janus may not be fantastic at sniping eco structures like other factions fighter/bombers but that doesn't mean they suck. Like the UEF T1 bomber it is about using them for the right job. E.g. Abuse their AOE and high DPS to swathe large chunks out of your opponents land army for instance.
6. T3 UEF land is almost a timebomb and possibly the strongest lategame. Percival is borderline OP and a fantastic unit! Titans are shielded raid lords of destruction. T3 UEF air is the same as all the others. T3 air (excluding Shocker) is about as perfectly balanced as possible.
7. Sure the T1 UEF frigate might not be the best (like cybran) but it has jamming. T2 UEF destroyer might not be the best (like aeon) but you have the shield boat. T3 UEF navy more than makes up for any inefficiency in the earlier stages and is very powerful.

At the end of the day, it really comes down to how you use the pieces of the UEF army. Each unit can be viewed as a tool designed for a specific job. Use it for the wrong job and it's effectiveness drops.

To all those like myself who thought the Aeon sacrifice system deposited 100% of the units mass into the build project, prepare to have your preconceptions shattered.
Here are the results of my meticulous sandbox testing. What you do with this knowledge is up to you.

General disclaimer. All test were conducted 2 or more times. Most only two times.

Tests using unupgraded SACUs (except for sacrifice). Note: Mass of sacrifice upgrade (150 mass) not included in calculations. Also HP values rounded down to the nearest hundred.
GC (27500 mass): 90000/99999 HP for 27300 mass of SACU (#14)
Paragon (250200 mass): 2100/5000 HP for 251550 mass of SACU (#129)
CZAR (45000 mass): 30700/40000 HP for 44850 mass of SACU (#23)
Tempest (22000 mass): 46200/60000 HP for 21450 mass of SACU (#11)
Salvation (202500 mass): 4700/10000 HP for 202800 mass of SACU (#104)

Tests for RAS SACUs (not preset) with sacrifice. Note: Mass of sacrifice upgrade (150 mass) not included in calculations. Also HP values rounded down to the nearest hundred.
GC (27500 mass): 25500/99999 HP for 25800 mass of SACU (#4)
Paragon (250200 mass): 600/5000 HP for 251550 mass of SACU (#39)
CZAR (45000 mass): 9300/40000 HP for 45150 mass of SACU (#7)
Tempest (22000 mass): 12500/60000 HP for 19350 mass of SACU (#3)
Salvation (202500 mass): 1400/10000 HP for 206400 mass of SACU (#32)

Tests for RAS preset SACUs with sacrifice. Note: Mass of sacrifice upgrade (150 mass) not included in calculations. Also HP values rounded down to the nearest hundred.
GC (27500 mass): 84400/99999 HP & 99999/99999 HP for 25800 mass & 32250 mass of SACUs respectively (#4 & #5)
Paragon (250200 mass): 2700/5000 HP for 251550 mass of SACU (#39)
CZAR (45000 mass): 36100/40000 HP for 45150 mass of SACU (#7)
Tempest (22000 mass): 47500/60000 HP & 60000/60000 HP for 19350 mass & 25800 mass of SACUs respectively (#3 & #4)
Salvation (202500 mass): 6200/10000 HP for 206400 mass of SACU (#32)

Tests using T3 engineers as sacrifices. Note: HP values rounded down to the nearest hundred.
GC (27500 mass): 24200/99999 HP for 27768 mass of T3 engineers (#89)
Paragon (250200 mass): 500/5000 HP for 250224 mass of T3 engineers (#802) = 202680 mass worth of reclaim from wrecks alone.
CZAR (45000 mass): 7400/40000 HP for 45240 mass of T3 engineers (#145)
Tempest (22000 mass): 11300/60000 HP for 22152 mass of T3 engineers (#71)
Salvation (202500 mass): /10000 HP for *** mass of T3 engineers (#) <- Test not conducted. Got bored.

My general conclusion. NEVER use the sacrifice system unless you literally have no other choice. Its better to ctrl+k and reclaim the wrecks.
Have fun out there.

@FtXCommando Please try and find a more constructive way to say what you want to say. Sarcasm and thinly veiled insults are not conducive to a productive conversation.

A mod to play as Nomads in the Co-Op missions. If there is another way to accomplish this outside of a sim mod, let me know!

Sercammus faf mod to not break all cycle type hotkeys (e.g. for factories or templates). In this mod I like the ACU info card, construction prediction times and mostly ECO stall predictions on constructions.

What about allowing the ACU to "walk over" T1 units like EXP's? That way the effect is symmetric (i.e. easier to understand for newer players) and with clever micro, you can still obstruct a retreating ACU with early T2 units.

For a bit of "fun" I decided to go back in time to Nov 10, 2016 on Github to a release by Zockyzock. As far as I can tell, this is the first record still in existence of a balance patch for FAF. If anyone else can find an earlier record, please let me know.
But I decided to scroll through the changes, just taking note of changes to Aeon. From what I can gather based upon the buff/nerf ratio, Aeon must have been silly OP on the steam version of the game. Did anyone here play SupCom:Alliance on steam? I would love to hear about your stories about the gameplay, especially if Aeon were as OP as they seemed from looking through the FAF balance notes.

But it was rather ridiculous how quickly the blaze could move.
I would still like the Oblivion AOE to be increased to match it's graphic.

@FtXCommando Please try and find a more constructive way to say what you want to say. Sarcasm and thinly veiled insults are not conducive to a productive conversation.

I would like to see the T2 PD for Aeon get an AOE buff. It's tragic how the animation and AOE do not match. Its overkill is so terrible, a little buff to AOE might mitigate this "feels bad" aspect of the structure.
Also increasing the projectile AOE on the T2 destroyer for Aeon might be a good idea, but it would need monitoring.

Perhaps SACU's being identical to ACU's is the final answer to the long-standing question of "how to balance SACU's"? XD

V3 is the bees knees! Very cool and love it. Thank you for taking my suggestions on board and for taking the time to fix EVERYTHING*! That can't have been a small task. Seriously impressive stuff.

There is one major problem with your mod. Whenever I look at a YT cast of a game, I feel blinded by the obscurity of it all. Everything morphs into one indistinguishable blob. Totally wrecked my enjoyment of watching FAF casts

*Those idle factories and their grey outlines hovering on top of other icons is a little janky. Also SMD can't count to 7 haha.

Looks and sounds good so far.

A couple of thoughts.
If you are appropriating code from UI-Party, make sure that the cycle bug isn't present. This bug caused hotkeys which cycled through selections (e.g. factories or templates) to reset periodically (on some tick count) to the first in the selection. One example that happened frequently was cycling through intel structures (from radar to select sonar), only for UI-Party to reset me back to T3 radar when I was trying to build sonar.
Instead of left clicking to unpause, can you change it to right click? My logic is that right clicking can toggle paused/unpaused, while left click selects all things in that expenditure category (useful for manually implementing a partial reduction of expenditures).
Also, why did you decide on green/pink bars for eco, not the traditional green/yellow? You could also use the colour wheel to invert colours for paused vs unpaused eco representation. E.g. Green (mass) and yellow (energy) for current expenditure, then red (mass) and blue (energy) for paused expenditure. You could honestly just make colour customisation another setting (so many settings :/) by taking some code from 4z0t's ScoreBoard. Their UI mod probably has all the code you'd need for that.

Your idea of integrating eco managing via thresholds and profiles is inspired! Usually eco UI programs are full automation, or full manual. The hybrid approach should really help with getting a balance between the two while maintaining user control and preference.
In a similar vein, could you add a feature (e.g. clicking mouse scroll wheel) to set a category (or any project really) as maximum priority. The mod will then pause everything else (with some selective logic of what to pause first) so that you don't stall on what you must complete ASAP.

The auto activate function seems amazing! I understand why cybran ASF's have it off by default, but it makes no sense if you are overflowing. Same for seraphim selens.

As for how to represent all this functionality on the UI, you seem to be on a good path. The idea to keep a display of how much a paused category would consume if turned back on is a really nice touch.

For things like profiles and settings you can shove most of them under the hood into the wrench icon (top left of your image). Stuff I'd put here include:

• TML missile storage limit.
• Specific threshold for each category to control which units gets autopaused first.
• Profiles.
• Autopause mass thresholds.
• Ordering of prioritisation order. This can be it's own sub-menu where you click and drag icons into an order you like. Similar to kiddy coding programs with visual code blocks.
• Set autopause/prioritize only, or ignore some, specific units. Can be integrated into the above UI sub-menu as I binary "include/ignore" tickbox.
• Auto activate unit abilities. On/off setting. A more advanced version might have aa on/off setting for each unit.

For many things in the above list, you can use a similar UI layout to the Eco display itself. Or just appropriate code from 4z0t's mods as they have implemented submenus, sliders, drop down menus and tick boxes.

For things which will potentially need to be adjusted in-game on the fly, they need to have a designated keypress and/or UI element. An example of this already implemented would be the left/right click of the eco display to pause/unpause stuff.
These include:

• Expandable subcategories. This can be represented as a dropdown menu which automatically opens up when the mouse is hovered over the main category.

Those are my quick initial thoughts. Shove most out of sight, and only worry about what the player is likely to want to use differently every game.