Well, your own comments seem to describe USC better in terms of your wish list. USC and UCB are both elite universities. USC is private and has far fewer undergraduates. UCB is public and has far more undergraduates. They both have very nice campuses.
Many - even just taking one major at an UC - find that it takes 5 years to finish a Bachelor’s Degree due to the extra required GEs and distribution requirements and trouble coordinating classes, etc. Plus the class sizes tend to be larger. Many are primarily taught by TAs.
Meanwhile, at USC, it is very common to be able to accomplish double majoring or having 2-3 minors while still graduating on time.
Neither of my daughters or any of their friends applied to UCs or even considered it, but they were also OOS. Personally, I had very little interest in sending my daughters to any state university, but that might have changed if we were CA residents, as California actually has great public universities. That is not really the case in FL. As OOS, we never even considered any UC.
As I have mentioned on this thread before, I would suggest taking a look at the Niche College Rankings… comparing USC and other colleges and universities using some of their rankings, metrics and measurements. The Niche Rankings and Grades are mainly based on survey results from past and current students and faculty, and they delve into a number of areas that really highlight the topics that will most impact you once there as an actual student on campus.
For those curious… USC ranks #19 overall on the Niche College Rankings and its grades are: A+ for its Overall Niche Grade… and then by category: Academics A+, Value A+, Diversity A+, Campus A+, Athletics A+, Party Scene A+, Professors A+, Location B+, Dorms A-, Campus Food A-, Student Life A+, Safety B. But here is likely the best indicator… USC is ranked #1 out of 1579 colleges and universities surveyed in terms of “Best Student Life” overall.
Good luck reaching your decision…