I’m not sure you can get campus parking permit at UCLA if you are underclassman (freshman and sophomore) when you stay in a resident hall. You should know UCLA campus is much larger if you already visited both schools. I don’t think the surrounding area is a such bigger issue since you don’t to West Hollywood by walking through Beverley Hills. You can ride Metrolink to Santa Monica from Exposition Line. There are 3 stations around USC campus. I went to high school in Pasadena and made to both schools and picked USC because of the scholarship. For some reasons, people in SoCal give more prestigious to USC if you do care.
Where did you get the idea it is difficult to get your desired and required courses? I was in one of the largest departments the school had to offer not once did I not get the course I needed nor wanted. You will always get the class you need.
To say the alumni do not do anything for one another is really nonsense. Bruins are extremely close to each other and we all take pride in our school, so please stop giving false info. That would be like people saying the "You earned yourself into UCLA but bought yourself into USC. Or, “You were rejected from UCLA and had to settle for USC.” That wouldn’t be fair nor nice, would it?
Yes, we do have a large student body but as I said that means nothing. You do not even notice it. I’ve been in courses where we’ve had 300 people in the course and yet, you never missed a beat with the course and your professor always made time for you.
For undergrad, USC. You’ll have more opportunities at USC in smaller class settings where you can get to know profs better. You can get lost in required courses at UCLA where you might be one in hundreds of students. You can always attend UCLA for for grad school.