I have an idea, how about when you are a lord or king you can ask another vassal to travel with him, if you are a lord he may agree if he likes you, otherwise he will refuse, if you are a king he will always agree unless he really dislikes you, it would work similar to being enlisted but there would be no promotions or extra equipment, and you would receive no salary, instead you would get relation boost with that lord for every battle you participate in, how about that?
