I'm an old Civilization fan, and recently I have enjoyed playing Paradox's game (Crusader Kings, Europa Universalis and Victoria). They touch the same spot that Civ5 wasn't able to touch.
Seconding this. The latest Europa Universalis game is eating all my time while I conquer South-East Asia one nation at a time. Imagine a Civ game with twice the depth and ten times the run time.
My neglected partner hates it.