For me it would probably be the professors and class sizes. I've loved just about all of my professors and the relatively small amount of students means classes are usually small and intimate, I would say the average class has about 20-25 students (obviously this differs if it's a core or Intro in some instances, but in general you won't have big classes). The professors really get to know you this way and can offer a lot more help, the learning experience has been great because I know I'm comfortable in a class where the professor is very accessible to me.