The key to this team, obviously, is getting puvis going. Boatright is going to score his 18-20 and Hamilton, by the end of the year, should be playing aggresive enough to drop 15 a game. Brimah will be up and down, but should be able to score 8-10 a night just on lobs/fouls and Facey should be able to get 6-10 just on 0-bards. that right there is almost 50 points. This team doesnt need to score more than 66 to win most nights. Getting 10-14 per game from Purvis is huge and to do that you need to define his role better.
I would start Samuel at the 2. Your starting lineup is excellent on D and you can put Boat off ball for a few possessions and let Samuel find him, Hamilton and Brimah. Then when Purvis comes in, hes coming in as a super-duper Samuel of last year. There is less pressure and he can focus on D, pushing pace and getting into the teeth of the defense. Really though, if this team brings the defensive intensity it brought to the duke game to every other game, they wont lose more than 4 more games all year. Whether or not they get roles defined on offense will determine exactly how well they do.