I think it depends upon what you want to do... going with a group of guys to hang out and enjoy the game, I'd say the following about places I've been:
1) KSU - Aggieville is one of the best spots I've been. Great bar scene and lots of fun. Town is small, easy to get around and people are great
2) PSU - great tailgating. Stadium and happy valley are separated so doing both is a hike. Wearing Nebraska gear I was treated to items thrown at me, repeated fight challenges as we walked around and plenty of number one salutes. If we did not attend the game with a few PSU fans I would not have stuck around. Won't ever attend again
3) KU - good small town for games. Nice bars, people want to have a good time... easy to get tickets
4) Univ of Ill - similar to KU but more spread out. I had a good time there. Liked their stadium as well. Easy to get in an out of, bathrooms lines were small and we were welcomed most places we went.
5) Univ of Missouri - meh is my first reaction. tailgating is fun but the place turns into a waste dump. You literally are driving through trash and sometimes pushing trash to get out. garbage cans/bags are not used. fan base is mixed bag and the town itself is just ok. I've never got that college town feel, but we mostly tailgated when going to columbia
6) Michigan - AA is a great college town. Between the golf course, bars and great places to eat it is one of my favorite places to visit
7) MSU felt like Univ of Ill to me, but I liked their stadium less. I'd probably put East Lansing behind Lawrence and Champaign but it's close. We enjoyed the bars and people were very interactive (in a good way). Most people I know have EL rated higher than I have so I probably missed parts of the charm.
8) Washington - Seattle is a nice city to visit. I always have difficulty with colleges in big cities because they don't feel like college towns. You basically experience Seattle and then add a game on a campus to the event. I do like Washington's stadium and the views are terrific. But it's not a college town feel
9) Northwestern has the same issue. In fact, outside of the visiting Chicago and access to cheap game tickets, I'm not a fan. Their stadium is probably the least desirable of the stadiums I've visited, the campus is just ok on game day. You basically visit chicago and then travel a long ways to attend a game.
10) Univ of Nebraska - campus is located downtown so their is a great bar hopping scene. Plenty to do, but tailgating is limited compared to other locations. People are overly friendly and buy visitors drinks. Stadium is ok. If you sit in the more exclusive seats, you have a lot of amenities. If you sit in the cheap seats in the end zones, you have a walk for everything.. including bathrooms. The stadium is not laid out very well... if I'm honest.
11) Pitt - another experience like NW and Washington. Tough to judge. Since the game was at the steelers stadium I never set foot on the campus. That game did not feel like a college game at all.. more of a pro game day experience. But tickets were dirt cheap.
12) USC - Stadium is close to NW as the worst. LA is spread out and there really isn't a location fans all gather to interact. It's back to the city vs college campus feel. We did have our beer stolen during the game.. actually, they poured out the beer and took the cans. You have a lot of solicitors selling watches, tshirts, etc as you tailgate as well. USC is historic but not sure I'd do it again.
that's my brain dump.. as I listen to this conference call.. lol