I go the other way. I think if they are going to have play in games it should be the last eight at large teams.
If the NCAA tournament is going to keep the "little guy" story line then let them experience the actual tournament. Not the fake one in Dayton. Let the BCS level teams that can't crack the top 40 even with all of their advantages play the play in games.
The little guys have plenty of opportunity to avoid those 16 seeds. They end up there because they honestly dont really deserve much of a spot in the tourney (theyre being put into the last spots in the tournament, and lets be honest, there are multiple at large teams that get left out that would be better than the 15\16 seeds most years, so really youre talking about sub top 70 teams). I have no problem with 'little guys' getting into the tourney, they can make things fun, but only the ones that actually deserve those spots. Winning an awful conference (or worse, not even winning it and just having a couple lucky tournament games) doesnt really mean much if you couldnt put up any quality wins.