Yeah, I play in a SW RPG group too, and although the group is fun, it's pretty evenly split between Jedi and dark jedi. The only non-jedi characters are support NPCs, mostly around because we don't know how to fly a spaceship for ourselves.
Actually, I lost my character after the first time we played, so when I made another, I gave him piloting skills, just so we could be slightly more proficient.
It is a fun group though- there's me, a light-side consular, an ewok guardian (also light side), and a new player who ended up as a secondary jedi consular (light side). Then there's a second new player who's going to darkside guardian route, a four-armed guardian with a perchant for force choke (who's going major-darkside), and finally the leader of the group, a jawa who does just enough darkside and lightside stuff to balance out.
We do spend a lot of time discussing whether or not we actually see the darkside jedi using darkside powers. So far we've demanded that one of them surrender his lightsabers until he can meet with the jedi masters, but the other guy isn't far from it.
-kv