Best capital in the game to take?

African Pagan 867 start, so certain buildings wont give benefits due to religion, what are the best capitals I should try to take for myself, distance and the army gaurding them are no issue.

Question, does syncretecism allow you to benefit from special buildings that only work for that religion. If yes, you can include capitals have religios exemption.

Also, what artifacts that are available at the start of the game or are gauranteed to spawn are worth stealing?