I didn't watch college basketball last season, but I saw Hasheem face Roy Hibbert the year before and Roy Hibbert always seemed to have Hasheem's number. Hasheem was EXTREMELY limited then offensively. However spending all 4 years in college must have improved his offensive game because he averaged 13.6 ppg and I kept hearing how improved he was.
He is limited offensively but if utilised in the right system with a good point guard, his height alone will be worth 10ppg reasonably efficiently. I can't see him ever having the ability to average 20+ ppg, but it will improve throughout his career.
If given starter minutes I expect 8ppg, 8rpg, 2bpg in his rookie season, with his ceiling being somewhere around 15ppg, 10rpg, 3bpg