I see nothing in his actions (or play, to be honest) that make him worthy of being the next captain.
From everything I have ever read about him, he is very difficult to get along with. He may be the leader to some on the court, but he never did it by himself. He is also clearly not a leader off the court, with reports of clashes with teammates and coaches alike.
I'd be very surprised, shocked even, if they name him captain this season. Let him have a season as the true "leader" of this franchise and see how he responds. Would anyone at all be genuinely surprised if he sulked and acted up if we start the season terribly?
This team needs a better roster, not a captain for the sake of having one.