Secret Asian Man has an interesting commentary on racial drawing styles in this week's comic. I agree, I do tend to make black folks with really wide noses, although if it's a drawing of me, it's justified. However, I do notice in superhero comics if folks are drawn right or not, because they are trying to draw in a hyperexagerated realism, so if someone looks wrong, it is really noticeable. In a more cartoony style, it's less noticeable, but still, my advice would be to try to practice drawing a variety of faces, like people should try to draw a variety of bodies as well