Small sample size but when Johnson was out this season for a few games, Smith was great as a first option, do-everything player. In four games, he averaged 25.1 pts on 50 percent shooting, 11.5 rbs and 3 assists. He led Atlanta to impressive wins against Oklahoma at home, on the road against Indiana and a close loss to Miami on the road. He was fantastic in those games and great down the stretch. I'm not saying he would put up those numbers for a full season as the no.1 option, far from it, but it's possible that he's one of those players who needs the ball a lot to maintain a rhythm and perform to his best.
On the Celtics, I'd like to think the best will be brought out of him next to unselfish and great passers, that he'd flush a lot of alley-oop dunks and fix his bad shot selection. But I'm afraid he would also take a lot of mid-range jumpshots because that's the lovable system we have here.