Oberlin College (Oberlin, Ohio)

We just did the college search with our daughter, who is also interested in pursuing a career in creative writing. Two schools not on your list that I suggest looking at are Oberlin and Kenyon, both of which are eponymously named for their respective Ohio towns. Our daughter chose Oberlin, where she is now a freshman and having a great time. 

Two others, both in downstate NY, are Bard and Sarah Lawrence. None of us could relate to the social scene at SL, but it has a very strong writing program. Bard was definitely a top contender for her, but in the end Oberlin just felt more like 'home' to her.

About weather: Personally, I don't think it should be an elimination factor, *especially* for California kids. Everyone should have the experience of real seasons for a few years.

This won't answer all of your questions but you might take a look at Oberlin and Kenyon, both of whom have strong writing programs. Kenyon, especially, is known for the writing program. Brutal winters for both of them but the kids seem happy at both. Lots of BHS kids at Oberlin and I know of one at Kenyon, though there may well be more. Oberlin reputed high on the quirk factor.