What I think would make a big difference would be divorcing Mentorship from the class system....
Exactly, mentorship should be divorced from the class system. As rulers would choose one or more mentors, ruler-appointed mentorship must be divorced from the class system. Otherwise, ruler appointments could violate a player's inalienable right. Ruler appointment would also follow the medieval focus of the game. Should anyone of that time get to opt into such a key position?
I simply want some assurance of quality. Ruler appointment
might accomplish this. However it is accomplished, allowing advanced players such as Indirik to be mentors would assure strong new players.