So how come characters in anime are more often drawn as European Caucasians than
Japanese or Asian?
Because the anime style is based off of cartoons brought over by GI's.
Manga characters originate from Betty Boop whom Tezuka based on while searching for art to make his own as well as Disney characters.
Manga grew from that and anime followed suit.
I'm not going to bother explaining anything more.
Whites are just more attractive in general.
Do you see how simplistic anime characters often are? You are simply inserting your own biases and viewpoints into anime. Nips see Nips, Europeans see Europeans.