Well, for me, leaving California was really one of my top priorities. I had never wanted to stay there for college and was actually really surprised that so many of my final choices were indeed California schools (Berkeley, UCLA, Stanford, etc.) As soon as I was able to remind myself that leaving had always been a majorly important thing for me, the choice became more clear.
However, I was also concerned about the state of the UCs. They’re running out of money, classes are huge, and there is very little student-teacher interaction (unless you seek it out). Because I was a Regents’ Scholar, some of these problems would have been solved, but not all of them. Being a double major (which I was sure I wanted) would have been impossible to achieve in less than five years there, and it wouldn’t have been certain that I would have gotten the classes I wanted.
In addition, sometimes I feel like their selections of students are based too much on numbers. Barnard reads admissions essays first, and in my opinion seems to prioritize putting together a class of truly interesting people with amazing accomplishments and stories. This isn’t to say that you can’t find people like that at Berkeley, because there are plenty of fascinating people there, but just that nearly everyone I meet at Barnard has been (even if we don’t become friends) at least engaging to talk to. This was super clear to me at Admitted Students’ Weekend (I’m not sure if you went), when I met a lot of other people and talked to them.
The main things that won me over in the end, then, were:
1. Going to Barnard would mean leaving California and starting a new, awesome life and having excellent adventures in one of the coolest cities on our fair Earth.
2. I would be able to get the classes I want and most likely be able to graduate with a double major in four years.
3. (Hopefully) I would have the opportunity for my professors to get to know me/at least know my name and to have teacher-student interaction more frequently.
4. The other students would be qualitatively chosen, and from what I observed would at least be interesting people to hang out with.
I also had a special case where I was more or less recovering from an abusive relationship, so I felt like it might be a good time to feel more empowered as a person/woman and spend some time focusing on myself instead of letting guys distract me. This worked, kind of.
Best of luck with your decision! Know that either one of these schools is lucky to have you (as much as I just trashed Berkeley, I still love it. Go Cal!)