I'd like to put emphasis on the Phodians and Kodians. Both are races already part of the Empire. While they might not appeal as PCs to many, it doesn't mean that they aren't worthy of being depicted.
I mean, I could see ways in which a Phodian caretaker could be part of a Star Army ship. They're great cooks, and on their homeworld they kind of have this 1960s Mafia vibe going on with gunslingers and such. There's a way to make these look cool if anyone tries to. Plus, so many ways to do "when pigs fly" jokes with them, seeing that they are feathered humanoid pigs.
As for Kodians... has anyone seen the Golden Compass? The warbears in there, they're pretty badass, right? Well, the Kodians are an entire race of those, except they're all gritty cybernetic high-tech alongside that too with a 'no pain no gain' mentallity. There's some serious badassery to be drawn from those too.
Also, the Miharu plot hinted at two races near its end. I'm still making those two races happen in time. That's a matter I already raised behind closed doors in the staff forum, so, I'll not elaborate further.