Short version Is usurping of new Kingdom titles best to integrate the a new kingdom into your realm?
Long version Starting as Norway in 1066 in my second game, i called back my invasion to rather try and consolidate a "scandinavian empire". After some civil wars, i have managed to have complete control of my kingdom where the succession goes to my oldest son instead of votes. To expand i have primarily used the claim county button on different Swedish counties. After some wars, i have the possibility to usurp the kingdom of Sweden. My problem is that i only have two, yet very strong duchies, in Norway, so it is difficult to get my son to inherent the kingdom of Sweden, as their succession are by votes. Maybe there are some tricks here i dont understand. But my question is, should i not usurp the kingdom of sweden? What is really the benefit of being the king of sweden as well as Norway, when i have it de-facto under my control? Could i just take all the territories and forget about the title?
Thanks!