I don't know a better living RTS that is diverse enough to reward my preferred playstyle and tactics.
This used to be Starcraft 2, I was waiting for the last great patch that never came (because top people became FrostGiant). Starcraft 2 had become repetitive and stale for me.
The brick-wall difficulty curve of FAF (1v1) is keeping me here quite well.
I agree with Zlo in that it is nice to be good at something. Im not like a 2k rated player but as i read somewhere on another post a while back even the 500 that only plays astro is still pretty good at the game. Also its super satisfying to be able to micro a strat well, execute massive build orders very fast, or win an asf fight with bad odds.
It is relatively nice to make content for, whether that is in the form of maps or mods 
A work of art is never finished, merely abandoned
Because the skill ceiling is sky high, there is always room to improve even for FAF's best players while at the same time the game is very satisfying to play even when you are not perfect. There are a lot of available strategies and so many little plays to be made each game. It rarely becomes stale if you don't want it to be. The community is nice and passionate, players want to not only keep FA alive but to improve it with each day. Finally the gameplay and game mechanics are like no other game with real time resource drains, reclaim and projectile physics. All of that creates a unique game that feels amazing to play and improve at.
The thorough design, with solid OOP principles, and the simple fact that almost every feature of the game is exposed to modification, makes it the most extensible code I've ever personally had the pleasure to work with. It's almost 100% true - if you can dream it - you can do it. That's unique and that's what keeps me at it.
The core reason? If you stuck a gun to my head and asked me "why Supcom"?
Because its Supreme Commander. I grew up on OTA. Its first RTS I truly played, I forgot why I migrated to Supreme Commander and later Forged Alliance (heck for the longest time I think my memories of FA were actually Supreme Commander Vanilla). I've tried other RTS, be it Warcraft III, AoE and its clones, Starcaft on N64 (that was an experience). But I return to Supreme Commander, why do I return?
Because Supreme Commander is unlimited, in what other universe set in an RTS that the game, is such YOU matter. Not a Heroic Character with Name, but you. You are the ACU, you are in the cockpit. And the scale of the universe, is that YOU don't matter. Its a thousand year world, fought on practically infinite worlds, across time and space. Nothing YOU do matters, so YOU be anything you want to be. You can do anything, be anyone and the skies the limit. And their the core game design, its inituitive by beyond inituitive its seemless.
One of the flaws in Starcraft or AoE is "Build More Farms/Build Additional Farms" or how non flow-eco gameplay interacts with the gameplay. If I need 100 mass to buy something outright waiting for 100 mass 'slows' down the gameplay. A flow eco enviroment like in Supcom means you are never needing "100" mass you only need a mass income = to what your consuming and you stall, game doesn't stall. I can a unit while stalling at 90% it just takes 10x as long. Its only downside really is the tech system in FA Vanilla is inorganic. I tech up a factory but it doesn't 'mean' anything. A mod like EngiMod however solves that beautifully. As now Support facts make the transition more seemless. Now I have issues with EngiMod (not balance onces philiosphical ones to be clear). People like to say Starcraft is constant 'action' that true but that because of how the game itself works. Due to how I described backqueing is bad as you essentially spend resources without spending them. In Supcom the game itself core lends itself to things constantly happening.
And what Sprouto mentioned did you know Warcraft III, has a hard coded 4 faction limit? Legit its impossible to add more factions to the game w/o removing a base game faction. I have a clear bias here, but think about what that implies for a second about the game code.
I’m a shitty 1k Global. Any balance or gameplay suggestions should be understood or taken as such.
Project Head and current Owner/Manager of SCTA Project
I starten playing becarse i liked Vanillesoße and make firebase and pew
Then i found faf and Played to make experimentals on Dual gap.
That objective Quickly changed to making t3 MeX. Then I tried to get good at dual gap to farm big rating to be able to get into the biggest lobbies. Notably I got so good at Finns that I killed nexus, check pornhub for historical evidence. The amount of hate I received for my big rating number was very faf like, I got kicked from every lobby because I was considered overrated. Foley was the prime proponent of that and I developed a one sided love relationship to foley. My objective then was to get better than foley, and in my books I tied him at least. This was roundabout the time when I lost interest in last trying too hard, there was still the objective to get 2k ladder which I tried for a few weeks, but ultimately I didn’t have the time anymore to grid enough to memorier bos and moves required to succeed on that level. Maybe I’m also too old or too bad.
It was always nice to play with yudi, and trying to pester him a little, but he is an alien and I don’t consider competition fair.
Nowadays I merely play to reconnect to the lovely people of faf and make a big play from time to time, but the way balance goes this is not intended anymore to happen.
Yeah these days I’m merely here to remind people of the futility of war, religion, guns and Donald trumpet and to talk shit at FTx and his cronies.
I played ta when it came out, was the best game ever. You guys ever play boneyards galactic war? That is still the coolest multiplayer I've ever played.
When I heard about supcom and the upgraded over ta I bought it when it came out. Played it untill FA came out, never bought fa but I did play a few matches online. Absolutely loved everything about supcom.
A couple years ago I saw a gyle cast, and was like wth is faf?
With the ta gameplay, supcom upgrades such as easy engie management and strategic view, along with faf upgrades such as engie mod, ui, and unit balancing, there is not a different game out there to play
I've played SupCom on and off since its release back in 2007. A big appeal for me is that it has had something for a wide variety a play styles or level of investment. What I mean by this is that back in the GPGNet days I was playing some other games more competitively with some friends and didn't really take this game that seriously, I just liked having massive survival battles or going through the campaign with different and usually troll strategies or self imposed limits like air only or defensive structures only. On the opposite side of that, much more recently I've been on a kick to start getting better at this game instead of playing chill games with zero effort or improvement and it's amazing the amount of depth there is. There's something for every level or type of player in this game.
Some more specific stuff:
I can't say it better than it's already been said by all the people in this thread, but here goes
I like the scale in particular,
from the outside looking in, the scale is daunting and then, once you try it and become accustomed to it, it's hard to imagine being without.
the immersion is another big one.
a majority of our awareness of the simulation happens subconsciously, it's something appreciated as a whole rather than as one particular interaction to point to, and yet pointing to the single interaction is the only way you can show someone else it's there, but the reason it matters is for the general feel.
The amount of situational turnaround in a typical game, the variety in gameplay and the sheer quantity of emergent gameplay and strategy.
The constant learning curve and the constant unexpected tricks/tactics/strategies used against me. I always feel like a beginner (in a good and exciting way) and I've been playing for 5+ years. When I get wrecked the feeling is usually "wow, how did they do that, i must learn that" as opposed to "i never had a chance".
The full map zoom is something you cannot live without when you play other rts and the constant rebalancing of units with the updates to the client etc shows the constant evolution of the game. In no way has this game reached its peak and I dont see it reaching it anytime soon. i honestly believe if not for the single thread on cpu bottleneck issue then this game would be a top esport game.