Vicky 2 in its current state is Paradox's greatest game pound for pound. It is also the most difficult to grasp as the population "POPS" and economic mechanics are unique. There is a lot of finanical management with central banking, taxing, tariffs, supply and demand for the factories. The Combat is also great. It has frontage and unlike EU the units have experience. Also since all your military units are comprised of actual POPs of your country, you will feel the hurt on your total population if they are annihliated in combat. I once lost millions of men in an epic world war having mobolized most of my workforce. Its cool seeing your population counter go down 100k every day in a verdun like battle.