With western psuedo-anime style shows I think they have a problem with 'over consistency' if that makes any sense.
Take Death Note for example, characters can have very well defined noses and sometimes the same characters can have very simplified noses depending on what is needed moment to moment.
While in western shows there is a narrow range the animators are willing to have their characters be in so in they look accurate to the model sheet but not right for the specific moment.