That's actually what worries me about Whedon's approach. I saw an interview where he said that what interested him about Batgirl was exploring what "her damage" was that made her want to be like Batman. That's missing the point. The essence of Batgirl is that she chose to do it without being driven by any damage, that it was just the right thing to do.
I usually wind up disagreeing with you on these sorts of things but on this one I am in total agreement.
I view Batgirl as sort of Batman "lite". If there's any angst to her it comes from her being a copycat/wannabe and always needing to prove herself.
The Huntress is the Batman-esque character with a rape origin story (1989 version at least).