One bad habit that has surfaced itself a few times so far is that he doesn't love contact on offense. I don't think he is soft, but I think he is trained to use his talent to evade the defense and/or shoot over them. I though he had an opportunity to turn the corner and challenge the defense at the rim, but that's just not his game atm. He prefers to fade away and avoid the defense. He is going to make those tough shots at a higher rate than most, but it's not going to be more efficient than attacking the hoop. He rarely did this in college, but he had some moments where he lowered his shoulder and invited the contact. If he can start doing that more it will be a massive development.
I'm not sure if this is a habit you can unwind, but he's got youth on his side.