I think pop-ups telling us of people who are of ages to get married would help a lot. Otherwise it's easy to forget about a family line. Maybe random events where a certain family has gained a lot of followers and you have to convince them to let them send over their children for marriage. That could be a mini game of some sort?
Edit: Also, I think adding the ability to have someone added to a couple to break that apart and making that a fighting match of some sort would be another cool minigame.