I expect AJ to stay with the team. Despite his lack of contribution to the team, I believe we'll see, although maybe not directly, his contribution in the playoffs. When Harris loses his composure in a few games in the playoffs he'll come in, calm things down, and make some hard fouls.
For Croshere, at the beginning of the season, I fully expected him to be moved because his expiring contract makes him a lot more valuable than he can possibly provide on or off the court. Although the mavs may keep him with this new attitude of monetary conservation cuban seems to come under.
As far as who I'd want in their place.... well no one comes to mind. Detroit is big man heavy with the signing of Webber so we could possibly see something there. I think the only thing we really need is a low post scoring presence, which I dont think we could get for Croshere.
With all that being said, I hate to say it but I see us doing nothing and getting closer to the cap at the end of the season. This would at least give cuban a bit more pocket book space for any future contract negotiations with current players.