This is why CK2 is the most fun Paradox game.
I cant agree as CK is actually my least played Paradox game, I am an HOI guy!
But I do think CK is one of the best games from a design point of view. Both CK and HOI have focus that is lacking in EU.
HOI is purely combat and map painting (playing Axis is literally designed to do WC, its historical!). All its systems are designed and focused on combat and conquest, so there is purity of design and it is a great game, it knows what it wants to do.
CK is the same, the focus is creating a dynasty, psuedo RPG character building with a bit of map painting conquest on top. Again all the systems work towards this and make a great game.
EU has a split personality problem, you are supposed to build an empire (its the age of empires!) so there is all the conquest, but to keep things semi-historical/balanced there are all the mechanics to slow you down. Now the game says stop map painting! Do other empire stuff! Eg. Trade, colonising, diplomacy etc. The problem is all these systems are incredibly shallow, tedious and boring (mostly result in clicking on buttons with timers, to get money/mana.)
So there will always be this problem with EU. They have to radically redesign basic systems that model things such as internal empire management. The estates system was supposed to do this but its a terrible failure and should be scrapped or completely reworked. As both Vic and CK have, there has to be fun and challenging gameplay that happens during peace time to make the game more dynamic. At the moment once you have enough hours in the game to understand all the systems and realize how shallow it is EU basically becomes a TW game minus the real time battles. And thats just pathetic. It has potential for so much more.