I would like to see something like modul training. Something like you can add one more single player you wish to a specific training session. Let's say you want to train your point guard in passing (single training), while you think one of your bigs should receive that training, too (added player).
As for supporter: Jersey, hell yah, would be great. Probably changing appearance (for us narcists here) of the player, too.
Draft must improve more. If I spend the most possible cash every week I want to have clear and complet information about a rookie.
No new tactics or so. Keep the game as simple as possible, it will help that newbies won't give up after just signed in.
The method of learning Japanese recommended by experts is to be born as a Japanese baby and raised by a Japanese family, in Japan. And even then it is not easy...