So, the Hardholder isn't great at killing people or making people do what they want or getting shit done. They can do that a bit, but they're not the best at it. But! If you're playing a hardholder, you're probably playing in their holding, and you're probably playing members of their gang, and what they say about those things, and what the hardholder is like is going to have a big effect on the fiction of the game.
If you're playing a Chopper, you're better at getting shit done. You can fight and kill pretty good. You've also got this gang and what you say about this gang, and what you're like, is going to have a pretty big effect on the fiction. Not as big as the hardholder, but pretty big.
Gunlugger, you've got no gang, and no holding, and no crew, so what you say about the world pretty much only applies to you. But when you want shit done, you can get it done.
Now, the battlebabe is different. You've got no gang or shit, but you're not as stone-cold deadly as the gunlugger (close, but not quite). What do you get instead? Who's more likely to be the hero of the story, the gunlugger or the battlebabe? Who is going to make us sit up and listen closer when they're in the spotlight? Who does what they want and damn the consequences? Who can start trouble and then just leave? Who is this story about?
Like, if you've seen Kick Ass, we all remember Hit Girl more than the dude in the wetsuit. That's my take on mindshare effectiveness, but maybe I'm all wrong. I still couldn't tell you exactly what qualities make the Battlebabe this way (though I'm guessing the sex move is part of it), so I would like to hear more crazy-talk.