I don't know... I only play Kingdoms.

Do your guys gain experience? Do you have trade markets, bazaars, and town halls?

I think they're probably mostly cosmetic and based on flavor. Then again, I've certainly never had demons. But I'm probably the only guy here who doesn't care much about that thing they call "magic".

 Yup, Pariden's Ally is the starting tech line. I don't think there's anything comparable in brute force to ogres and the like, but note the Kingdom group techs give larger groups, so they might be able to make up the difference by numbers.

yah but they get DRAGONS. Evil Kingdoms...

Overall, I think that the Kingdom tech tree just makes more "Sense" and it flows a lot better and just feels more well designed and natural. Fallen tech trees are "leaps and bounds" with more critical technologies being unlikey or harder to get, but having overall better rewards. It still just seems less well put together.

I prefer, for the most part, the kingdom tech tree. And therefore Kingdom cities.

One really painful thing about the Empires tree is lack of access to materials, you don't get that +4 materials building, so unless you're lucky enough to find wood you can struggle with materials. It pretty much forces you towards using the big beasties, umberthingies and devils, as they cost gold only (lots of it).