Lately I've been enjoying the vikings. I play a faith-oriented game with a few cities, so having strong holy sites is essential. I think only Australia and maybe Poland can rival the adjacency bonuses of Norway. In the picture, you can see a holy site with baseline adjacency bonus of 15 - 3 from the woods, 6 from the snow pantheon, and 6 more from the stave church. Add in the double policy card and it's a game changer. Even this small city with only a farm and camp was able to build the Mahabodi temple in under 10 turns (standard speed).
Also, I like Ethiopia (rock-hewn churches are my favorite improvement), Poland, and Mali. Vietnam also a historical favorite but less so since they nerfed the unique encampment.
Rome is my least favorite, but I also dislike Maya, Korea, Kongo, and Babylon. The Mayans are supposed to be the tall civ, but in this regard they get an F from me. Kongo can't even found its own religion (yikes!), Korea is boring, and Babylon is way too much of a weird gimmick.
There are doubtless others I like and dislike whom I left out. It's great there is a large variety that caters to different tastes.