Not bad, but at just 20 and with only allstar potential, I would suggest training that guy in some passing and 1v1 forwards, to improve his handling. Both of those will reduce his turnovers (which if you think about, each turnover counteracts each rebound, yet PA and HA will be free). Also, I think jump shot up to ~10 is near free for centers, or at least takes very little potential, so you could add that as well. Then cap him by pumping IS (or more ID/RB if he's intended as more of a defensive big man).