Mudiay is a guy I've got my eye on. I'm hoping he keeps growing. Currently 6'5, but he's 18 yo with a 6'10 father. Looks like a real two-way threat, though we don't exactly need another guard.
Okafor looks like he'll put up beastly numbers next year, but I fear that he won't translate too well. Bully ball is easy as a high schooler, and doable in college, but really tough in the NBA. He doesn't have the defensive upside I'd be looking for in a C. Al Jefferson is his ceiling, but he's probably not as skilled as Big Al.
Towns also lacks a bit of defensive upside, but his shooting ability give him more appeal compared with Okafor. If he develops a reliabe 3pt shot it's really valuable in today's NBA, and he even play as a mismatch PF.