The classes can be huge in freshman/sophomore classes, 200 or more, but as soon as you start hitting junior/senior classes (especially in physics or math or other sciences) the class size drops considerably, and professors will start to learn your name. Office hours is a great way to get to know your professors and get help.
My favorite class would have to be anything with Adrienne Steinacker. She's a great astronomy teacher. My least favorite class...well I haven't had a really awful class yet, though Onuttom Narayan's classes are very difficult.
It depends on how often students study. I wouldn't say they study more or less than average. A lot of students start homeworks as few days before the homework is due, unless it's really hard. I probably study more than the average student, and I study almost every single day except Friday night and Saturday.
Physics students are pretty out-spoken, so there are usually lots of questions and comments (sometimes annoying, sometimes really helpful).
UCSC students do seem more interested than usual in learning outside of the classroom. People talk about important relevant issues, like science and technology in society, or the environment, or politics, or social issues. They really seem to care.
Students can be a little competitive and they can be a little stuck-up. But most are very, very helpful, willing to help you and show you what they did, etc. There's always the few who are elitist, but I'd say the majority are nice and friendly.
My major is physics, and I love my department. The teachers--while some are hard--are so far all at least nice. They will help you if they can. You'll work for a good grade--oh yes you will--but they'll help you as much as they can. Most of the administrators--especially Hua, who is usually the undergraduate adviser for physics majors, though she's out on leave right now--are great.
I don't usually spend time with my professors outside of class, unless it's at office hours. Sometimes I'll stick around after and chat briefly with them, but usually I'm far too busy.
I think that UCSC has a pretty good academic requirement, but here's a word of advice--if you're transferring in, make sure you finish the IGETC, otherwise you have to finish UCSC's General Ed requirements, and that can be a real pain in the butt, because they do require a lot of GE classes...on the other hand, a lot of classes can satisfy up to three requirements in one shot, so you don't always have to take one class for each requirement.
I think the education at UCSC, from a physics standpoint, is pretty practical. They want us to get internships, they want us to do research, so that when they release us into the world we'll do better, whether we work or go to graduate school. Some teachers, I know, change the class schedule and lecture time to focus on things that are important in physics right now so that we'll be better prepared to work in those fields.