I doubt we'll see her, but I don't really see why adding Leslie would ruin anything. I mean, whether the mediums are different or not, the character suddently was made part of his past in the 70's, and no one blinked.
And we saw like, five minutes of Bruce's childhood and the aftermath of the murder of his parents. Surely, there was something else that happened in his life to influence him, even if he doesn't think about it every day. I would present Leslie as something Bruce has all but forgotten, and remembers, and it really affects him moving forward. I really don't think showing some scenes of Alfred, Leslie and Bruce in the past would feel all that forced in context.
This wouldn't be a "SPIDER-MAN 3" revamp, just more of Bruce Wayne's compelling story.
What I would do, and this isn't exactly foreign territory to comics readers, is have Bruce realize that his war on crime needs to involve stopping crime at the source, and bettering the lives of Gotham's unfortunate to prevent the breeding of criminals, and I would use that to improve his public image, which was tarnished in BEGINS, and starting to become a bit more respectable in THE DARK KNIGHT. Leslie Thompkins would be tied to that, as would Selina Kyle. Heck, I would tie Hugo Strange to it as well, if I had my druthers, and have done so in a script or two.
t:
It'd be nice to see other areas of Bruce's skill development explored than just his stealth/combat training. The escape artist stuff he learned in that episode would be great for some of the Riddler's traps I imagine, and Leslie would be a great new confidante after what Bruce had been through and continues to go through. Plus there's a spot open for a new female presence since Rachel is now gone. I like Guard's idea here.
