What about kingdom titles?
Meaning: how many do you have?
I think I only OWN two right now, but presumably when I die my non-primary heirs will magic the other 2 in my De Jure into existence.
The Kingdoms In my De Jure are Sveden, Norway, Finland, and Denmark. And I am exactly one county away from having all De Jure territory of Scandinavia.
Also, Is it weird that my empire's primary source of income is vassal rebellions? :3
Ah. 'Cause having Kingdom titles pass to all the pretenders... kind of a pain in the ass for a few generations, even moreso if you either lack the diplomacy (or a decent spymaster) to have guys not join factions against you, or the martial ability to field bigger armies. Also, if they rebel, their claims get passed on to their heirs... just extending the annoyance.
This is why, in my most recent game, I have 3 castles in my capital county. Lots of tax and enough levies to deal with most things that happen (albeit only really on the British mainland and Ireland, but whatever
) though god damn are they expensive to raise.
I've never been into assassinating people (and certainly not close family members!) but you could just murder their council every so often, make sure they aren't all that good until after all the reputation penalties pass.