I think generally its hard to find a match because not everyone is the same. Some aren't interested, some are more clingy, and yes, people with a good balanced personality are usually taken. Not to fear, you just have to get the right person at the right time. Its the same for both men and women so we kind of know what you are going through
Where have you been looking? You should take up some classes and get yourself involed in school clubs and make some new friends in classes. Good girls usually don't get involved in bad activities. But, still..don't go actively searching for one!
i think its not working out for you because you have too many high expectations, you shouldn't have expectations at all really and just let things flow on their own, like when you meet a girl stop trying to analyze her thinking is she your girlfriend material or not, don't rule her out or give her a score, what if she doesn't even see you in that way or has a boyfriend already, what if she's just trying to be your friend, just try to be friends with girls and get to know them as a person, no one gets a girlfriend/bf overnight...things happen when you LEAST expect it, when its meant to be...
dont categorize girls or follow stereotypes, treat everyone as an individual, everyones different and unique once you get to know them.
youre rushing into things and making quick judgments, the day you stop doing that and are open minded about meeting not just girls but people in general, getting to know them as a person without expecting anything in return, you just might meet your dreamgirl.