I was going to open up the "Jeremy Roach" thread, but might as well put this here, since all offseason discussion about Duke basketball should revolve around Roach. I don't think there has ever been a season so heavily leveraged on one player's potential improvement, with the (probably solid) assumption that K is not going to look too hard at transfers. We have obviously had seasons that hinged on one guy, usually NPOY-caliber guys, but never on the absolutely necessary improvement of one guy to this extent.
The good news is that Roach actually shot pretty well for the entire 2nd half of the season. Over his last 13 games, he shot 39% from 3 (18/46). That's not very high volume for a guard at Duke, but it's certainly encouraging, and it's not very low volume.
His FT accuracy is not really worth analyzing, since he got to the line so rarely. Getting to the line more in the first place, rather than the FT accuracy, is an easy area for improvement for him, given how elite he is at finishing - 61% FT at the rim puts him up there with the likes of Tatum, Kennard, Tre and Grayson (and much better than Tyus) at Duke. Anyway, he shot a little under 75% from the line for the last 13 games, which is respectable and indicates a decent floor on his 3pt shooting.
His assist/turnover over the last 13 games was 1.75. That's fine, maybe even good, for a fairly raw freshman you expect to see great improvement from, especially with so little offensive competence around him by Duke standards.
After taking a look at his numbers in an optimistic light, I think there is potential for him to be great next season. He has the statistical makings of the kind of guard who traditionally destroyed Duke's defense, who can drill 3s if you go under screens or tear you up with penetration and very good finishing/passing if you go over screens.
The problem with Roach for next season is the floor is much more important than the ceiling, and he has a huge range of possibilities as a sophomore. Duke won't need an All-America point guard to win the title, and it might even be harmful to put a guard who warrants 30% usage on next year's team - Banchero is going to want and probably deserve close to 30% usage, and Griffin is going to probably deserve 25%+. Duke does, however, need a competent point guard to win the title, and risking the season all on Roach's floor is not something most rational people would do.
It would be like telling Zoubek to miss the 2nd free throw intentionally in 2010. Only an alpha champion would go that route.