well the problem I see with training this guy is his inside shot. It's awfully low, and he's small, so it takes longer to get it up.
So a superstar...unless you go 100% for him, I don't think it will become.
100% because you'll have to sacrifice some other things, including money you would get for him when you would just train him for money and not to become a star.
but okay, the next draftees are not sure calls yet either, and besides you don't have them yet, so you just keep training this guy untill you see your new drafts and then decide which road to take.
as for expanding your stadium, it has nothing to do with training, nothing at all. You expand when you have some reserve cash, and your arena isn't big enough already. These are the only two rules that you need to look for to answer that question.
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