He's too fragile still. He won't be drafted. One more year of refining his defensive skills and getting bigger/stronger. He needs to stay, no matter what the team plays like next year.
Only because he plays at Memphis. I really doubt he would get drafted if not late 2nd round.
I have seen him play and as a NBA GM I would not spend money on him. Better players in the NBA or in other developmental leagues to fill out the roster if needed.
Whether or not he justs drafted... unsure. Whether or not he survives in the NBA... surely not.