She's a terrible "female anime stereotype" that encourages girls to be whiny, obnoxious, spoiled, and prone to throwing temper tantrums. She also causes body image issues in girls, and, I can't keep going on like this. (by the way, I am not making this up. Someone actually does think this way, however absurd)
I'd like her to come back too in some way, because she was a great character that really broke the mold for active female main characters on this show. It'd be a shame to see such great character development and potential go to waste.