Singles sites

Since I am single, I have been on various singles sites for several years. Out of all that time I've had one woman that I was friends with for a while, but as I said in another post, it didn't go as I would have liked. Generally it seems that women are a) too far away, b) too young or too old for my preference, c) many ads have not been updated and they have not visited the site in a long time. I have some requirements, but I don't think they are unreasonable, especially when it seems like more is required of the men they are looking for. Non-smoker, honest/considerate, and a least halfway fit (I want us to be able to get out and DO stuff together), are really my only requirements.
I have other preferences (like I would prefer with out kids), and in my area, as I don't really have the means or want to move far. I can be flexible, but I can't seem to be shown the same consideration. One woman flat out demanded that it was MY responsibility to more for her. Like I move hundreds of miles for a stranger. Right.
Most women seem to want someone taller them them. In a way I can understand that, but it out right eliminates me as possibility, because it isn't something I can change, and they can't be flexible.
They want nice looking guy. Again, understandable, as I would like to find a nice looking woman. But it is open to interpretation, and it seems their wants are actually needs.
They want a father for their children. Not unreasonable. What puts up a flag for me is when they are 28, and have 3 kids, the oldest being like 10 or something (rough example). Means she was almost a kid herself, and she didn't learn anything from the first one. I have a moral/ethical problem with this. It also puts a question in my mind 'Would she be loyal to me?' I also have to wonder what kind of morals she has. Not to be mean, but I don't want to inherit someone else's problem.
Anyway, maybe singles sites have worked for some people, and I'm glad for them. Their effectiveness for me remains to be seen. I guess I'm just in the wrong area or something. As I said, only one kinda worked, for a bit, until she couldn't be bothered by me anymore.