Hands down the three best SEC towns are Knoxville, Nashville and Athens. Although Nashville is more for other things than the college teams.
After that, Iowa and Nebraska have passionate fans but towns aren't that great. Columbus, so-so. Happy Valley a tad better. I would imagine Madison, Boulder and Seattle (Washington) would be fun. Austin, Berkeley (Cal) and Palo Alto (Stanford) if you're in to weirdo radicals. SoCal sucks.
All the Service Academy towns are cool, especially Colorado Springs.
Arizona and Research Triangle would be nice locations too.
Logan Utah (Utah State), would be one of the more breathtaking for beauty.