Basitlla is in the game but she has very shot appearances.(Wish they put more so the 2 games would click more together)
If you say that revan turned to the darkside then in korriban,in the sith academy,in uthar winns old room(the one you have to blow up with those charges) theres a sith holocron inside with a recording of bastilla telling you something.
If you choose ls revan then after you do the ravenger she talks to you with carth.
I know not much at all