calderon - expensive, useless going forward (in comparison to cost), can't defend, totally unnecessary except as a $10 mil mentor.
bargnani - i still think he can be an excellent nba player, but we need to move in another direction. time to set the tone of this team, and it should be different than the one he sets. i'd only get rid of him for something decent in return, though, not just to get rid of him.
barbosa - offensive black hole. too small to adequately defend position. i hope he declines his option hoping to lock into something before the new cba.
impossible but would want him gone:
kleiza - redundant and not effective in terms of the way we want to play. he's injured, so this is a pipe dream.
i don't think anyone else really needs to go. we just need better players around many of the guys we already have. this will be a long-ish rebuild. i expect to be terrible again next year.