I don't. I mean I'll grant that Rachel Dawes in Batman Begins more useful then any non-Catwoman girlfriend of the previous four films, but they're predominably ciphers.
Just how did Rachel serve any purpose in "Batman Begins"
besides giving background information on plot developments and characters and being a damsel in distress? At the beginning, she supposedly has important conversations with Bruce about himself, but basically she's just providing back story for him. Then she talks about Jonathan Crane throughout the movie. Then Batman has to save her from The Scarecrow. Seriously look at her dialog. How is she not a cipher?
"Deep down you may still be that same great kid you used to be. But it's not who you are underneath, it's what you do that defines you."
"Your father would be ashamed of you."
"What chance does Gotham have when the good people do nothing?"
"Isn't it convenient for a fifty-two year-old man who has no history of mental illness to suddenly have a complete psychotic breakdown, just when he's about to be indicted?"
"Falcone floods our streets with crime and drugs creating new Joe Chills everyday. Falcone may've not killed your parents Bruce but he's destroying everything they stood for."
"In prison, he shared a cell with Carmine Falcone, he learned things and he will testify in exchange for early parole."
She barely has a single line that isn't exposition. She's practically the narrator.