Yay! This sounds great! I haven't read that many AUs, but ones that were historical that I remember liking were--well, obviously yours but I assume you tried to be doing it right! I loved that Star Trek fic where they were in the old west. That seemed like a great example of how much you can say about the character with the way you transform them.

There was also an ATLA fic that I was really loving but I don't think it was finished...damn, who wrote it? Rawles! It's unfinished, but it was called "A Certain Fondness." An Avatar Regency fic.

Those are the ones I remember feeling were really taking place in those times. A Certain Fondness didn't get very far, but iirc it was already dealing with the some of the social pressures etc.