I'm 30 and never been married. I plan to someday. When I get a stable job making enough to support a family I hope God will bless me. I have heard of some people being 40-45 before they got married. I hope I don't have to wait that long, but at least I know that I still have a chance. It is never too late. I wouldn't mind marrying someone who is younger than myself as long as it is the right person. But generally I look for someone who is about the same age or maybe even a bit older.
I'm not sure if there is a right age for getting married. If you meet the right person and you are still young (18-22) then be very thankful that God has blessed you. I think a lot of people don't get married that young especially men. It is hard, at that age, to find a stable enough job to support a family.
I think women generally look for financial stability. But then again, I am not so sure. Perhaps a guy who works 40 hours/week at minimum wage would be acceptable to some women. I personally don't see a problem with it especially if the guy has plans for the future. But women tend to want stability right then and there, and they don't usually go by the what the guy says on these things.
The sad thing is, it is becoming harder and harder in this day and age for young people to get married. Our economy is structured in a way where many people find it hard to get a full time job. It used to be a lot better. Nowadays, people can only find part-time work because most companies don't want to hire too many full-time employees since they have to fork out more benefits if they do. I would say it isn't until much later than 20 years old that men are able to finally get to the point where they can support a family. Unfortunately.