I'd rather see a scruffy pirate faction.
Mainly, it would open up a huge amount of map possabilities with a minimum amount of extra overhead work.
If you go with clone wars-era, or any other era stuff, not only do you need two completely new factions; you also need era-specific
*Weapons
*Starships
*Droids
*Static map objects
*Voiceovers
*Texturees,
etc
A pirate class, based during the Galactic Civil War, gets my vote. I'd love to see Y-Wings with pirate markings, mash-ups of Rebel/Imperial starfighters, and lots of cool little extras like a Slave I to spawn in, Headhunters, etc.
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