I'd train his Inside Shot and Inside Defense up to 10, so he can be a decent starter in weeks with tough games. Then I'd train as much of Passing and Outside defense as your games allow you, until both are at least mediocre. Doing so will increase his value on the field and also on the transfer market, because bigs without secondary skills are worth nothing.
Once his passing and outside defense are both 5, you can alternate training inside skills again as well as Jumpshot for forwards. In weeks where you have 2 very easy or too hard games you can train passing and OD further.