Funny enough, I think that of the 3 rookies Mickey is the one least likely to stick in the NBA (despite the obsession with him on this board). His size is likely to be an issue -- he lacks the offensive skill set to be effective as a stretch 4, he struggled to defend guards on switches in college, and he's small to be defending in the post.
Rozier, though, has shown a lot the past 2 games. His athleticism is off the charts, his size doesn't seem to be as big of an issue as I expected, and (if nothing else) his defense should keep him around in some capacity.
Despite Hunter falling out of the rotation, and getting beat off the dribble often... he has good instincts, his length is helpful on defense, and I just don't think he's figured out how he fits in offensively yet. Seems he was mislabeled a "shooter" and is naturally more of a scorer.