bein_hasdorim:
I agree with your points and would just like to add the following:
In my experience, older girls that are working usually become disenfranchised with the way the older boys in the yeshivish world act and conduct themselves. These girls, as you mentioned, have become independent in one degree or another. However, most of the older boys are still in yeshiva and have not had any experience in responsibility. As mentioned in other threads, there are still boys in their late 20s+ who still have their mother making decisions for them.
Further, most of the older girls are working, and have been doing so for some time. They are used to a lifestyle where they can go shopping and spend money as they please. They, therefore, look for the same in a guy, since they would want to start a family and have to stop working at some point. This, I regrettably have to say, has not become the standard, rather it is the exception, in our society. The “men” believe that the women should still work, while 9 months pregnant, to support the household while they sit and learn, or if they have finally decided to obtain some responsibility, while they go to college to earn a degree.