Rebounding, raw size, athleticism. I've always tended to be lower on these big guys, simply because there are so many of them and few value in playing two of them together. The game has changed; post players are not worth stockpiling and are fairly replaceable when they aren't elite.
So that begs the question: what are the odds Sharpe becomes elite? If somewhat high, or the path is evident, then he might become worthy of a first-round selection, the four-year investment in his development. If not, it might be best to wait until the second round to gamble on a guy like him.
From my perspective, Sharpe is more Bismack Biyombo than Andre Drummond. Sure, he's a good passer, but his elite trait is rebounding and being catch-and-finish near the rim. I don't see the perimeter game really developing. Motor and effort are great, though they aren't requisite skills for a first-round selection. Roy Williams took a slight shot at him as he announced his declaration, saying that he can become great "if he only is willing to work a little harder and listen a little more." Roy doesn't say shit like that a lot. It really got me a tad skeptical.
I have Sharpe as a middle-to-late second-rounder, just because I don't see the upside a ton. I've been lower on these guys than most, so there's a real chance I do miss the boat. But I'll be alright with that; I'd rather swing on a high-ceiling, multiple-impact wing or guard than continually chuck darts at the big man board year after year.