Sure, agree 100% about putting folks in a box. I think basic traits are with us from birth, but preference, life experience etc makes us all a little different...I've always enjoyed time to myself since I was young. I'd just "vanish" and I gain energy and inspiration from the inside out mostly. I knew that way before taking a test, but after taking it, I thought, Mmm, so that's why I've been like that...extroverted folks gain energy from being around people; I love people and helping them (I'm a nutritionist) but if I can't sit alone and "ponder" I get rather depressed and drained...
I think your views are quite balanced - we're all a little nuts...