Wait... you CAN'T kill Quinn? I debated for a long time with my LS sith warrior whether to kill him or not because, LS or not, you can't have a traitor who tried to kill you hanging around your ship. Not with my wife-to-be on board, no way. I ended up keeping him because my SW was a goody-two-shoes but really, really couldn't wait until I re-rolled DS. Here's hoping they put it back in with a clear warning to all the ******* complainers.
Killing companions is just about the most impactful, awesome thing you can do in RPGs. Remember Mission and Big Z? Hands down, the best dark side moment in Star Wars.