I've been contemplating this myself lately, and I think...
She has to be spunky and outgoing to balance my withdrawn and cool attitude. Our outlooks don't necessarily need to match as I'd like her to be her own person, even better if they're a loud mouth with a fierce drive to prove themselves right. It'd be boring to be with someone that agrees with me on everything - I like a little fight in others, and I am a fighter, so it'd be perfect if we can butt heads every now and then without one of us losing our marbles. And of course, the basic things like having a heart and putting others in front of her before herself.
If she can pull it all off while still being a mystery, I'll fall head over heels.
Don't care about looks. Never have.
Bonus points if she's the kind of gal that can appreciate some destruction. We can set some fields, houses, and castles on fire and watch the world burn from a mountain lair~