Playing as Sweden, have Finland, Novgorod and Livonian Order as vassals. I've already began to vassalise Finland as Finnish is an accepted culture in Sweden, however due to the size of my other 2 vassals (especially Novgorod as they have all their cores) should I annex them? My experience in the game is little and thus I'm not sure whether or not the cost of changing culture in all those provinces would be detrimental or if that culture will just simply become accepted. Advice would be appreciated.