i think you missed bgurl's kobo showcase. she's got an attitude alone that would burn most of the scrubs in the online battles.
also check out the bgirl in this vid:
Shining: A short film by Moshen of Skill Methodz
...and those are only 2 recent, online examples.
in general, girls don't have as much testosterone as guys but that only takes away a small, top portion of the moves list. tops and footwork don't require great strength---only swiftness, flexibility, and other qualities both genders are capable of. everyone has a style waiting to be created.
also, physique isn't anywhere as near important as rawness. just bring the fire and people will be in awe regardless of how you look or who you are.
perhaps you haven't found any impressive bgirls because your exposure is limited. in which case, we should remind ourselves that the scene is predominated by a male demographic. therefore, you've probably associated bboys with the standard when really, the standard is not a group but a perfection: originality.