Indiana is the team I'm most worried about going after Smart. I think they could table a pretty big offer, and he makes sense on their team.
I'd actually be worried about Marcus being terrible in PHX. I don't know that he'll thrive on a bad team. He'll either immediately start turning the culture around, or I could see him trying way too hard, getting frustrated with his crappy teammates, and him missing a lot of games from injury due to trying to overcompensate for the plays his teammates can't make.