Bingowings said:
Besides Vader throwing his master down a death pit doesn't really redeem him, you would need another trilogy for that to happen.
I disagree. That is an act of personal redemption. He doesn't somehow negate all of the evil he's done, but he does, in those final moments, reclaim his ability to chose to do good after decades of being a slave to evil. He dies a man, not a puppet of the Dark Side. He doesn't need to go and build Habitat For Humanity or anything to accomplish that.
(Which is why in the EU it seems SO LAME that they name Han and Leia's kid Anakin. There's no denying that their father was one of the biggest SOBs in the galaxy)