Personally I'd like them to sign him to a 3-4 year deal. He plays hard every night, unlike some other players. He's steady, has a nice jump shot and can take it to the hoop. He rebounds and seems to play good defense within the Celtics system. I very rarly see him out of position and as I said he shows up every game, and seem okay with comming off the bench or starting.
Maybe Johnson can be that guy, but I haven't seen it. You know what you're getting with Bass. I see no reason why you wouldn't want to keep him on the team.