I think you have to mention budget in this one to get a better idea.
Otherwise, in general I wouldn't worry about proximity...with a car, SantaFe is not difficult to reach from anywhere. I know if I were 21 and living in gainesville I wouldn't want to be stuck out near the interstate on 39th avenue....I'd want to live near university, particularly I'd move to the duckpond region (but that's just me). During most times of the day SantaFe is a 25 minute drive away from there, and it's pretty darn far away by gainesville standards. I lived on north 6th st. and attended santaFe and I didn't even own a car at the time, and it was never a burden. FYI, I delivered pizza in gville (for about 6 years while I was there) until just a few short years ago when I completed my education after a 9 year stint in college

, so I could probably draw a detailed map from memory, haha.
From delivery driving, I know where pretty much every "bad neighborhood" is, so let me know what the range, and if distance or proximity to fun/interesting things to do is important (i.e. live near downtown - which I highly suggest, if nothing else, it reduces the need to drive after the inevitable drinking excursions that will ensue - she is 21 after all).
FYI, if you do decide 20th Ave/ 62nd blvd (around the mall) region, be careful there are some rough neighborhoods for women in that area to watch out for, particularly close to 34th st and near the mall. Also the tower road area is littered with places I'd rather avoid if I were a student. In addition, traffic is holy hell in the fall on 20th avenue and 34th st in general. As a gator fan, I'm sure you've experienced this before after a game.