I agree that if he came back to school, got stronger (which was a big driver to foul trouble), continued to work on the face up jumper / handle, feet work, and is ready to kill it, he could be a top five pick. He's got world-class athleticism, unreal length, impeccable timing on shot blocking, and would fit the model of today's NBA center if he could handle the ball a bit.
My struggle is with Calipari and his foot out of the door approach re: the NBA. I do think he's trying to dial it back but he's created such a monster that he's going to have to go in the opposite direction to stem the tide.