Most competitive Civ for Deity

Because maybe Poland on Pangea is better than Aztecs on lakes.

List of the best perceived civs in no particular order.

Totally depends on the VC you are feeling tbh with a lot of civs, but here's a list that are very good for at least one kind of VC:

Poland
Korea
Maya
Shoshone
Ethiopia
Arabia
Brazil
Huns
China
England
Zulu

people tend to rate the civs with science advantages higher since science translates to lots of other advantages.

personal preference: I'll take "interesting" civs with situational abilities over boring strong any day. I also really like synergistic and flexible civs like Shoshone, Maya, Arabia, Ethiopia

Picked The Aztecs because Deity level is about the point where their UA can really give the Polish UA a run for it's money.

Funny, I'm not sure if it was a conscious or sub-conscious choice to put Poland first on your own poll but I suspect you already know the answer to your question and that's why they are first on the list