...exuberant Prop 8 supporters on campus and loudly proclaimed their religious beliefs on creationism/intelligent design vs evolution, etc or somewhere in between those 2 extremes?

Athiests, Evangelical students, humanists, new-age students, Gay students etc can apply and get accepted and graduate at BYU with no problems if they're willing to figure out how to fit in. It's the same if an active LDS student goes to Stanford or Cal, if they are willing to figure out how to fit in they will be fine and can get a degree with no problems.