Well, about the loadouts and stuff, Trebuchets are definitely my favorite missile. Fast little bastards, strong firepower, and great distance in both covering distance and actually being able to lock. Definitely my choice.
I'd have an Erinyes with two UD-8 Kaysers and one missile bank with Harpoons and the other with Trebuchets. I'd also go with options two and three. Not too much maneuverability, but just enough to give you the actual ability to dodge an AAA beam
The action part couldn't have much more improving since it's already great and that is mostly up to the Campaign makers and such. Also, the ships do get boring after a while. The player ships are fine, but I mean the actual cap ships. There is only one Corvette for each race, the fleet could use some more destroyers, and the Deimos and Aeolus are kind of similar
But if you just meant reskins
They all could use a makeover!