What faction would you say is best for each tech level and each unit type? I think it goes
ACU - Seraphim. second most HP and the ability to have gun and tech upgrades make it awesoem early game. The seraphim T2 PD is also very good against T1 land. They also get double RAS whenever you want to go T3 air.
T1 land - Seraphim. IMBA T1 arty combined with decent T1 tank and IMBA scout place them here.
T2 land - UEF. Mobile shield combined with mongoose place them here
T3 land - Aeon. Harbs and shields rule the battlefield
T4 land - Aeon. GC will cost effectively beat all other experimentals and is the best against T3/T2 land. They also get a mobile shield. However in some situations the seraphim yotha takes this spot.
T1 Air - Seraphim. While Cybran get jester the seraphim bomber is better than the others in every possible way. Also get best transport for artillery drops.
T2 Air - Aeon. Mercy and swift wind combined with gunship that wastes very little DPS give aeon this place
T3 Air- Cybran. By a mile. Stealth. This just makes the Cybran airforce so much better than the rest.
T4 Air - Aeon. Czar beats asswasher and soul ripper any day because it is far more effective at sniping ACUS/experementals
T1 navy - Cybran. Frigate does not suffer from overkill and has the most DPS and does not waste all of its DPS in two shots like the aeon one does. Sub also has deck gun unlike aeon, fires torpedoes in larger slavos than the others overwhelming defences and does not in general suck like the seraphim one. Aeon do get AA boat however and this can cost effectively counter gunships. In most situations it also beats cruisers mass wise.
T2 navy - Cybran. Torpedo ACU with its reclaim ability and baracudas give them this spot. A stealthed cybran navy is hard to beat mass wise
T3 navy - Seraphim. T3 subs are hard to beat mass wise bar a nuke.
T4 navy - UEF. Atlantis over tempest any day. However this may change greatly if the temptest cost gets halved shudder
T1 Building - No difference
T2 building - Cybran. The best T2 PD, very cheap T2 shield, Best stealth gen, best tac missile launcher, best or second best TMD depending on the situation place Cybran here.
T3 building - UEF. They get ravages. Other factions don't.
Game ender - Aeon. But this one is very tricky. Paragon is very vulnerable to teleport and when it goes its gonna take your whole base with it but provided you keep it alive you win no matter what. Sera super nuke is awesome provided the opponent does not build 8 anti nukes and a mass farm to cost effectively counter it but it will still stop any land or naval attack. Mavor has lost its 60 mile headshot capability but is still quite good. Salvation will shred oncoming armies but is not all that effective against bases with proper shielding. Scathis needs to be close to the base to actualy be able to take down shields because at long range it will not hit the same shield twice. Because of this I think it is the worst. Overall I think aeon win this. They got two to chose from and also have the best T3 arty.