I agree about the Ewoks and Trandoshans, especially considering the importance of the Ewoks, but what bonus would they give if you took Endor?
Also, Coruscant is rather tricky. The problem with this world is that, if you include EU, the planet has been the Capital for four of my 9 civs - those of course being the Empire, Republic, Rebels, Vong.
What i think i'd rather do is have it being a neutral world to start off with, and have the Republic homeworld as Alderaan and possibly the Imperial homeworld as Kuat or Corellia.
This could also lead to interesting multiplayer game modes for things like 'whoever captures Coruscant first wins' and the like.
Dark Lord of the Purists
Inter Arma Enim Silent Leges