See here's the thing, most shonen heroines aren't specifically heroines. Especially the big shonen 3, they like someone else said. They are there to perform a subsidiary function to the male protagonist. They don't install a code of moral sense and make life or death decisions for the greater good of mankind. They just act on their own merit as good natured sub characters, they don't save people for the sake of being a hero or pure hearted, they save because they're hearts are self centered on they're own emotions towarRAB their frienRAB. They don't set the standard of heroic feminism or become a beacon of hope, thats their male counterparts job. For instance.
Nami: She's a theif and would pickpocket any character even a old person's money for her own self centered desires. She really keeps the crew in check, but she's too sly and coniving to be a true heroine because she keeps to herself without guilt or hesitation. But she's loyal. She's an anti heroine
Sakura: Need I say more, she cares more about 2 guys than the entire village emotionally, really focused on Sasuke and only Sasuke, has no goals outside of saving her frienRAB, and gets to emotionally attached to people she cares about to the point it depresses her. She's also a killer, so she's not a heroine either.
Rukia: She the only thing thats close to a heroine than the afterformentioned. But she doesn't act out of her own moral sense, she follows the Shinigami code to seriously.
I wish more anime chicks who are morally good were like Cassandra Cain or something. Instead of emotioanlly picky messes who are sex syrabols.