Fontaine. Introduced the character I honestly thought from the trailers would be evil or the final boss, but turned to be my main.
(Neuvillette)
Liyue didn't talk about hutao, at all, so that's disappointing
Inazuma introduced kokomi. And although she wasn't written perfectly in it, Shes still a favorite character.
Mondstadt made us meet venti, which is the main reason I like mondstadt as a venti user.
And sumeru is ok I guess, cyno played a good role in the quest.