I have learned from life that you don't need to rush as long as you know where you're heading and you are patient enough to work towards that goal. And there is no point to compare if you seriously know your strengths and passion. It is because you will succeed regardless of other people. :-)
To answer your question: at Stanford, you have to take at least 12 units per quarter to be eligible for financial aid, unless you have special circumstances (i.e. illness). On top of that, I think you can go on academic probation if you don't take that many credits... Stanford doesn't really want you to do undergrad part-time.