That's an interesting, but tough, topic. Off the top of my head, I'd throw these out there:
Mouring
Charlie V sophomore year
AJ senior year
Hilton senior year
Marcus senior year
If I had to choose one year that's very underrated and forgotten, it's Marcus. That 2006 team was so loaded and he was soooo good... I think people remember the overall feel of that season, which sorta skews how we view all those players.
No doubt that season was tough for all the reasons we know, but I remember Marcus being so money, passing, shooting and controlling the game. That, plus his brutal NBA career, I think skews people's memory of how good he was. He was the prototypical PG.
Because of the results vs guys like AJ, Kemba and Bazz, people don't remember how insanely good that dude was in college.