Just started playing SS recently, and after a short warmup vanilla game, grabbed the UAF and a few other mods. Just a few of my early thoughts on it while my perspective is still fresh.
1) The ship and portrait art are fantastic. Honestly it's the main point of the mod and it's great. It looks sleek and highly distinctive while still feeling distinctly in genre with the rest of the game.
2) from my relatively inexperienced standpoint the ships seem fairly powerful for their deployment costs, but not greatly so for a mod. Don't feel like I have enough experience with their line ships yet to really say.
3) Their fighters are gorgeous and I like the much more complex loadouts they field. The do feel substantially more devastating for their cost than existing fighters however. Using them from the vanilla assault carrier with targeting feeds seems especially devastating. The don't seem to have much in the way of weaknesses other than heavily overlapping fields of PD.
Honestly I find the vanilla fighters arather underwhelming, so these are nice, but maybe a bit far in the other direction?
3) I haven't yet used the infamous semibreve, but even the minibrev seems devastating. A heavy frigate outfitted with them seems capable of annihilating one or even a pair of heavy cruisers unless they field a sufficient dedicated PD.
Feels like they should either have their detonation toned down a bit, or perhaps a range reduction to force small ships to close to deploy them at greater risk?
Alternatively, making them dumbfire torpedoes with a proximity fuse that arms when the get in a certain minimum range of any enemy non-fighter and then detonates at closest approach would make the large radius of the blast a particularly interesting mechanic, with the expectation that they would rarely land a direct hit on vessels with functioning engines unless fired at dangerously close range, but would instead often do damage via the proximity blast?
One curious ?bug? with the minibrev is that the AI seems completely loathe to actually use the damn things. I had to fiddle with the settings of a separate fire control mod substantially before I could get my ships to start using them on their own.
Anyhow the mod seems just fantastic overall. At some point I'll need to do a run with the UAF as an opponent rather than ally and see how they feel to go up against. I'm guessing a heavily pd oriented doctrine would keep them from feeling too oppressive in general.