I love Lenny's list. Also,

Good self-esteem and love of self (not the same as self-centeredness).
Intelligence and ability to want to learn.
Sense of humor (everything is funny to some degree).
Someone who doesn't easily give up.

Much of this is based on up-bringing. So, if I would go back to my teen years - what I would do is try to spend as much time as I could with my gf's parents to learn their personalities as best as I could. I've found that almost all my girlfriends and my wife now have basically 'turned into their parents' to a large degree. This is something you can only cover-up so much - you will be like your parents so get used to it