Avatar isn't really medieval.Eh I guess but still dont like it.
The main series starts out with these sophisticated battle ships, gigantic drills and factories. They had tanks, submarines, airships by the end of it.
The start of the series is probably closer to 1870. Maybe something like 1850.
Cars being common, isn't that bizarre, 70+ years after the invention of the tank.
Technology in the world is probably largely held back by bending. People don't need to invent some fancy thing, because they can just hire someone to do something.
And probably some other aspects of religion in the world.
Additionally there was a lot of variety in the world. The fire nation has pretty sophisticated technology, the southern water tribe was very poor and they didn't really have much. The northern was much further along. Earth kingdom varied from place to place. Some places very poor, others not all that far off from the fire nation.
Air bender is way better in setting and writing.
Already seen 7 eps of Korra so far.
