What do you think of this?
Let the boys, who will be learning their whole lives, start dating at 18 (ben shmonah esrei lechuppah), and the girls, who will be supporting their large families and don’t have the obligation to marry early, get good serious graduate degrees and be earning decent parnassahs (maybe already owning homes) before they start dating. That would take them to late 20’s. Then the girls (sorry- women) would with Hashem’s help be able to pay their children’s tuitions, etc., and the boys could sit and learn with yishuv hadaas.