If you could change anything about the game what would it be?

Me personally would be the states system/cores and claims system. I don't really like the fact that with a press of a button, now that you've claimed to be the pan Slavic union or something like that, you don't have any resistance. For me It would be who owns it, ethnic makeup of that state, claims and for what reason, claim for the ethnic population living there for example, claim for border adjustment, claim for historical reasons i.e Hungary's claim on the parts of st Stephens crown that are not Hungarian majority areas. another thing related to this would be how there should be for authoritarian states, like the German Reich and the USSR, there should be the ability to move populations to be more historically accurate, this would make it so that the world will hate you but you have displaced the population. This probably constitutes as multiple things but kinda falls under the same umbrella