Well, I'm going to be one to actually try to answer this question:
1. Actually loves Jesus. Not a saint and far from perfect, but at least earnestly trying every day. Reading scripture, praying, worshiping, engaging in Christian, faith-filled/focused fellowship and mission with others. I'm try to do and be this, and need her (definitely in this case) to be the same to some degree. (If you've seen that thread of mine, I'm looking for a follower, not a fan.) [Not to say I can't be attracted to those who are not, but it's a fatal attraction that I'm working on extinguishing. Holy affections exchanged for unholy ones, with God's help.]
*SideNote* (Normally number 2, under a committed relationship leading to marriage, I'd say she needs to love me more than anyone else, but we're talking attraction here...you don't just start out loving someone, despite the 'true love at first site' people. I'd list 3 as God giving approval to both of us that this relationship, should we pursue and eventually marry, is okay. He approves. Again, though not exclusively, hard to apply when it comes to attraction.)
2. Something. Real descriptive, yeah...I get it. Still, there's something that happens between people. Call it chemical reactions due to pheromones, beauty being in the eye of the beholder, a spiritual connection...a 'click' ... whatever it is, there are some people we just endear to almost more effectively and instinctively than trying to force a relationship all the time.
3. Artistic ability (or at least appreciation). I'm an artist. Music is literally a huge part of who I am, and I want/need someone who can relate/share in that, or at least appreciate it. I find artisticness very attractive.
4. Personality. I m aware many people might feel this is unfair, but sometimes it literally just is that way you are (a person is) that makes them attractive. I knew a girl once who was adventurous, a dreamer/visionary type, open and honest with her wants and feelings, and really...just inspiring in a lot of way. I was VERY attracted to her, because she was a beautiful person. (In the words of "Falling for the First Time" by Barenakedladies, "Anyone plain can be lovely.")
5. Looks. They matter, and different people are attracted to different things. The thing is, if there's not physical attraction to someone, it's largely (in my experience and hearing from others) not something you can 'create'. I realize a large part of this is vanity, but it is what it is.
Sidenote #2: I realized while thinking about all this, that we can be really fickle. I might be looking for someone sweet and responsible, when I'm not sweet and responsible myself. I might be looking for someone who would get rated as a '6' by most people in terms of looks, while I might be a solid '4'. I say this, because we seem to hold double standards... Don't expect things in others that you aren't willing to do or be yourself.
There might be more, but honestly, after that... I don't know.. Intelligence, the ability to have fun and enjoy life...*shrugs*
Actually, I thought about it after posting.
6. Playfulness. (Please! I need a girl who can play around, laugh, flirt or banter just a little bit... something. Attractiveness points +^ ...and I'm an introvert, mind you!)