I don't know if it was somewhere before, but I'll take the risk to ask you guys this.
1.Can it be done so that titles will have to remain in possesion of generals genealogical lines?
2.Can it be done so that king and prince always retain a title for each of them of two surtain provinces (Sicily case: King - "King of Napoli", Prince - "Count of Sicily"). Like it were royal domains that always remain in the royal family?
When King dies, Prince will take Kings title(s) as he'll become a King and general that will become Prince will take Prince's title(s).
3.A general can only retain one single title. If he conquers a new province, its title will pass to the King and be taken back if there is a new general-family member that comes of age.
I really curious about this posible implementation.