I used to have a pretty good UI mod setup, and heaven had a good video on this topic of what he used and why
however, some of these are broken or now included in FAF by default and some new mods have been released also. For example the idle engineers mod is now broken.
what do you currently use and why?
Supreme Score Board: More versatile and useful than the default in both games and replays.
Advanced Reclaim Info: At-a-glance reclaim prioritisation.
UI Party: Start in split screen with sane layout. Nearly everything else it can do I disable.
I use No Shake as well only because once upon a time when I was a noob with 10 games a high-ranked opponent suggested it. I have used it my whole FAF career so I have no reference and don't even know if its still relevant lol
this is what most players use https://forum.faforever.com/topic/1186/ui-mod-guide-for-the-improving-player?_=1613225992111
Advanced Target Priorities 1.1 - allows you to choose what your units are shooting at. The applications are endless. But in particular: you can set your navy to prioritize destroyers so they will shoot destros instead of frigates. (Or cruisers, or engineers, if you want to pick off engineers around a navy factory)
You can set your ACU to target units, so you won't waste shots on the enemy ACU. Of course you can also prioritize the enemy ACU if you want. Depending on the situation. Or you can tell ACU to prioritize engineers if you want to pick off a few.
You can set mobile arty to prioritize factories while your tanks prioritize enemy units, so you can do max damage to the enemy
When you are telemazoring, and trying to teleport away, you can use target priorities to decide what your ACU is shooting at. Normally when you are teleporting you can't change targets because you can't give new orders to your ACU without canceling the teleport. So you can switch between targeting power and PD or whatever.
There are just a huge number of possibilities with that mod.
Selection Cost UI - this is mostly useful when analyzing replays. When you select units, it shows how much the selected units cost. This makes it easy to compare things like "how much total mass did I invest into my army, and how much total mass did my opponent have at the same time?" or "how much mass did I throw away when I lost this army group?"
Emperor_Penguin's icons (only covers ACU, nuke, TML and missile defences). See the icons here and find it in the mod vault.
Advanced Target Priorities - very useful for preferentially attacking certain types of units without extra apm cost
Disperse Move - niche use, but no real downsides to having it
NoShake - prevents screen from shaking from nukes/etc
Penguin's Icon Mod - makes ACU/SML/SMD/TML more distinct
Rheclaim - makes bigger reclaim sources more distinct
Selection Deprioritizer - makes it easier to select direct combat units without selecting things like engineers/t3 mobile arty
UI party is a must imo