The ones that don't use their teeth. I kid..
It really depends. I believe that the eyes are the windows to your soul and someone needs to give off an honest and good vibe. But at the same time a certain mystique is nice. Someone that's fun to be around, yet mature and who doesn't plan on getting wasted this weekend or something. Someone who has aspirations for their life and goals to meet.
As far as physical features: someone that's around my height, usually darker hair, brown eyes are nice, a sense of style, and a good scent (I'm a sucker for armani, polo, and nautica ).