Alright all factions get their evolution around a theme:
The big change to the GTVA since FS2 is the deployment of the Panopticon - a wide range surveillance device that acts as an early warning system, but also gives the GTVI the blind spot anxiety that starts the story proper. To match that the GTVA would have gotten pinpoint accurate weapons, such as laser snipers, single shot AAA beams and long range anticapital beams - if possible with some sort of blind spot build into the armaments to match the theme.
2. Terran Union
The Terran Union is busy "not being the NTF" and therefor would as a statement not have evolved their military tech from FS2.
3. non-Imperial Vasudans
They are on a quest for vengence so to match the theme, the non-Imperial ships would have all gotten really good at fighting up close and personal - with HP buffs and weapons that work really well up close, extra flak, shotgun-style lasers, big "point blank range or they dispate" plasma launchers and slow, long duration slash beams.
4. Solar Federation
The Solar Federation Military can be arrogant as all hell, and wouldn't touch you with a ten foot pole because you are from outside their solar system-sized gated community. They would have had a focus on range shooting, but different from the big sustained beams of the GTVA, so maybe missiles or railguns. In turn their weapons would have had a slight problem at medium range only to be better at close range because no touching allowed.
5. The Shivans
All evolutions of the Shivan tech would have been to match the Voc'quir tech, to stress that this time they are not dealing with the Terrans and Vasudans - they just happen to be there.
I wanted the Voc'quir to be much more close combat focussed - similar to the non-Imperial Vasudans - but to add them actually boarding ships into the mix. With no ships to base this on I am/was running on empty there then.