As I have played MUCH both games, I agree with OP.
I think I had similar fun from both EU4 and Civ5. AI in Civ5 isn't THAT incompetent, especially as there is <very sophisticated to create by team of best modders + one proffesional programmer> a mod which actually manages to GREATLY improve Articficial Intelligence.
Personally I would say both titles have some annoying and awesome features.
ANNOYING
- EU4 often feels 'very slow' due to it's real time and realistic, slow accumulation of power
- Civ5 offers active entertainment at every given moment but this is compensated by unavoidable huge turn loading times. I have a strong computer but ONE TURN (from 400 - 600) on big map can last 1 - 3 minutes. Literally three full minutes of waiting for all AIs to do their turn - now imagine you have to wait 20 turns for a world wonder or whatever, and you have nothing to do besides that...
- EU4 is based on military expansion, there is not much to do in peace
- Civ5 on the other hand while has cool military system it is much easier than EU one (due to nature of it and AI) and also it is logistical nightmare in late game. World Conquest in EU4 is boring, World Conquest in Civ5 is infuriating when you have to give orders to dozens of units each after another every turn... And one - unit - per - tile creates horrible traffic jams all time and everywhere
AWESOME
- EU4 is, after all, quite realistic and quite free simulator of Planet Earth in 1444 - 1821 period
- Civ5 is completely not realistic but absolutely free simulator of entirely alternate human history, on entirely alternate planet
I would rate both of them 8.5/10. I prefer warfare in EU4 - as it is often dramatic and difficult even despite mediocre AI. I mean, in EU4 unless you start with top global power or finally become one, you are always in danger of facing factions which can completely massacre you - this feeling of 'geopolitical danger' is cool. In the same time I prefer peaceful time in Civ5 as you always have lot of cool things to do in peace (always something to build, always something to 'terraform', Cultural Gameplay is amazing, World Wonders, World Congress, race for the victory etc)
Generally speaking, I am sure next expansion should GREATLY expand cultural/intelectual/administrative aspect of EU4.