Rarely heard of. I suspect the name of Oklahoma City is actually better known of the people around here, so I'm surprised by their stock of historic heritage.
This is excellent, though. They apparently take good care of it even though they're a moderately sized town.
I think Art Deco was cooler, or at least more flexible than Neo-Classical things because it allowed some classy buildings inspired by Native art and aesthetics.
Like this, quite possibly.
This looks originally American. Nothing of this style in Europe to my knowledge.
It's fine. Always good to have one's own traits IMHO.