Star rating to me is the most important, the more balls that player has the better his skill levles.
Potential is next, the more balls under potential, the higher his cap is meaning he can be trained higher than other players.
So in my opinion, I would take a 5 star 3 pot player over a 4 ball, 4 pot player. Keep in mind you never know WHERE the skills are going to be, so I'd prefer a player with better stats, so I could sell him easier and for more money should I not like his skill set. The only time I might make an exception is for a 5 ball pot player, those seem to be fairly uncommon, but if he is only 1 or 2 ball star ratings, he's prolly useless. But a 4 ball, 5 pot player prolly is worth it ahead of a 5 ball, 4 pot opinion.
Again, these are only my opinions, hopefully others will post with their opinions :)
This draft will be interesting as we have A LOT more control over our draft info at the end of the day. Instead of being random, I can know choose to scout guards, big men, or any combination. My list is so much better than last year!