Originally Posted by Knaight
…the Paladin is the odd one out.
As already discussed, the paladin works perfectly fine as an agent of the various city-state temple deities, as well as in other roles. The OP indicated he’s fine with opening up the alignment variants of the paladin, to better match with the different alignments of the temple deities.

Originally Posted by Knaight
It's really common in S&S for there to be 3 broad categories of civilization....
This may be true for that subgenre of fiction, but I wouldn't use that to restrict the cultures and polities available in a game world.

And those categories themselves are really caricatures, which contribute very little to a campaign setting and are best avoided.