I have to admit I’m not into the complex strategy games myself, because I dislike that the first 100 hours are just the tutorial. But I heard good things about Stellaris, although you need apparently some of the DLCs, so wait for a sale there. Endless Legends and Endless Space is in the same universe, but one is in space and the other rather based on fantasy. And I saw enough memes about Crusader Kings 2 to know that it is Crazy Story Generator in Medieval Times.