would be better off in the Big East. At least at first glance.
Assuming the Big East maintains it's automatic qualifying status for a BCS game, BYU could make possibly more money and be able to get better recruits in a BCS league as opposed to being independent. I've not looked up any revenue reports in making this assumption, but I'd think that the positives outweigh the negatives for the Y, at least from a pure football standpoint.