I think Henry Ellenson is a great example of this. I thought he should've stayed at least one more year at Marquette. Instead, he's barely getting into games for the Pistons this year in the NBA. If he'd have stayed in college, he'd have been the best player on Marquette (he would have led a VERY white team), First-Team All Big East, and seen as the poster boy for any tournament run the Golden Eagles may have went on this year. I think in nearly every case (there are exceptions) it'd be better for the player (and us CBB fans) if they stay in college and further hone their skills and become a household name. I just don't see the benefits of a guy like Ellenson or Stephen Zimmerman bouncing between the end of the bench in the NBA and toiling in the D-League. They'd be household names if they'd have stayed in college, and not rotting on the bench for 4-5 years until they get their shot, if they do at all.
Of course, I'm rooting for Allen and Kennard to stay at Duke for next year. If they both stay, they'll likely be considered (along with Frank Jackson) the best backcourt in college basketball. 2/3 of the guys in the best college backcourt white (and Wooden Award Candidates to boot), and playing for one of the most high-profile teams in Duke? Yes please.