Soon I look forward to adding four ARC-170s to my collection. One for each pilot. Doubt I'd get more than that even with generics. Add to them the Z-95 and the Y-Wings and you've got a Clone Wars fleet already. But let's talk about other ships:
LAAT/i
http://starwars.wikia.com/wiki/Low_Altitude_Assault_Transport/infantry
Another option for the Rebels. It would be a large ship with missile and crew slots, and I can see it having left and right auxiliary firing arcs or turrets. It may not be Canon any more, but I remember reading, and Wookieepedia seems to indicate, that the LAAT/i is affiliated with the Rebel Alliance. I'll also point out that, despite being a Low Altitude Assault Transport, it can be retrofitted to operate in space.
ALPHA-3 NIMBUS (aka V-Wing)
http://starwars.wikia.com/wiki/Alpha-3_Nimbus
I've already read some people suggesting this for the Scum and Villainy faction. But I can see this being an Empire ship. Basically a Tie Fighter with an Astromech, this is a likely option since (a) "it continued to see use under the Galactic Empire" and (b) I've seen three Empire Astromechs and it's possible there's more I haven't seen. This would give the Empire something new and a potential alternative to the standard Tie Swarms.
ETA-2 ACTIS-CLASS LIGHT INTERCEPTOR
http://starwars.wikia.com/wiki/Eta-2_Actis-class_light_interceptor
Darth Vader was apparently flying around in one several years after the Clone Wars. I'm not certain, as I'm waiting for Rebels Season 2 to be on DVD so haven't seen it, but I'm sure I read somewhere about Kanan and Ahsoka flying Jedi Starfighters. Might be the arrow-shaped version instead. Either way I can see an Empire version for Darth Vader, and a Rebel version of either Jedi Starfighter. Whether or not this includes Obi-Wan or Yoda is another topic, but I wouldn't rule it out. Personally, I'd like to see this as a box with three ships: Vader's black, with two Rebel coloured ships.
Perhaps, as one person commented on another topic, this could be an opportunity to introduce a FORCE upgrade. You get an Elite Pilot Talent and a Force Pilot Talent.
So those are my Rebel, Empire and potentially Rebel and Empire expansions. LAAT/i gives two side arcs/turrets. V-Wing gives Empire Astromechs. Jedi Starfighters give Rebel and Empire the new Force Pilot Talents. Not forgetting that the Jedi Starfighters also have Astromech slots.
What about Scum and Villainy?
They get two expansions in the form of Vulture Droids and Tri-Fighters. Not sure what they'd bring to the faction, except for cheap and agile Vulture swarms and Buzz Droid missiles, but I see this as being the most likely faction for them.
Now to the Epics. Oh yes, Epics.
REBELS
CONSULAR-CLASS CRUISER
http://starwars.wikia.com/wiki/Consular-class_cruiser
At 115 metres I hope this is kept in 1/270 scale. Ship is unarmed but can be retrofitted with a few weapons. I see this as bringing any needed fixes to the CR90 and GR75 while being it's own thing.
EMPIRE
STEALTH SHIP
http://starwars.wikia.com/wiki/Stealth_ship
At 99.7 1 metres it again should keep to X-Wing scale. There's also a Galactic Empire named ship, the Carrion Spike, which was a personal starship of Tarkin. Being able to Cloak an Epic ship might seem game breaking but I'm sure FFG will make it work.
So there you have it.
For gamers like me, I'd fly ARC-170s alongside V-Wings to recreate Clone Wars battles. Others will stick to factions, happy to have a cool prequel ship without having to deal with more factions or another starter set.
Edited by Rhosaarc