How about the best of both worlds? I went to a very large school...but they had ways to interact with people in smaller settings. They had something called a residential college where you could take basic classes right in your dorm. I was part of a women in science and engineering program that had special classes set aside so we could take them as a group with the same people we lived with. When you see the same people all day it's easier to make friends. There's also so much opportunity at a large school as you said. This happened to be university of Michigan which I highly recommend for in state students. Anyway check for these kind of programs at your large school.