I try not to judge people based on looks, however there are some things you can determine from them, like for example somebody who is fat and not content with their weight either has little self-respect, little self-control or not enough willpower to lose weight. Every person is different. As much as it pains me to say it, somebody who is religious (apart from mild Buddhism) I usually think of as less logical or less intelligent, even though religion shouldn't have any impact on how I see people (I'm agnostic myself and don't want to restrict myself based on something that may or may not be true).
But what I've just said sounds really cold. I don't really have criteria, I'll find the right girl when the time comes. Ever since a mistake (which I've learned from, so I don't regret it) I've been very cautious, for example holding off from going out with a girl who I liked and who liked me for three/four months to make certain that I really liked her and wasn't rushing into something (it turned out we weren't perfect for each other). I don't know what I want in a girl. A girl who is sweet, although I haven't met one before they're probably out there. A good music taste helps, but yeah I've got no clue. Someone that I get along with and can trust.
tl;dr: I don't know.