I believe Josh Smith can become a 18ppg, 9 rpg, 2bpg type player. I don't know if he will ever be a go to guy in the clutch, but he could become a good no.3 option type of guy.
18 pts may be a little high for him. I would say that may be his max potential. However he did show some very clutch 3 pt shooting the last two months of the season.
9 rbs per game is reasonable assuming he plays the 4. If he does play the 4 i think he can get 3 blocks per game with no problem.