I fell in love with that game because it has a simple mechanic which obviously not so hard to understand. As you appear in that world you don't have any goals and you just invent them by yourself and after some time you like that and find it very interesting.
Maybe that's actually one of the reason why not so much people know and liked about that game as they probably thought there's nothing to do,just in my opinion.
I liked that atmosphere which is fullfilled with a beautiful music and sounds. It's always that relax music with you when you check the political map,make trade agreements,send troops to enemies territory,build farms and walls,when you decide something and etc.
It has that alternativity where you as Cyprus (of course with a big desire) can conquer all Northern Africa or as Russia accept catholicism or playing as another country make a big move by destroying Vatican the centre of catholicism church. You could also play as Ireland or Italy or Scotland and some other countries and try to restore them or make of them full and powerful country.
I like so much about this game it's even hard to describe.
I hope that KoH 2 will come out that perfect as the first part or even better.