The niece and daughter should be the same person, named after the wife.

The problems I've seen the fandom up in arms about regarding her (in response to claims that Batgirl, Huntress, Catwoman, Talia, or any female in Batman's life who isn't simply a villain or limited to the friend/girlfriend role) is that most of the attention in the movie is on Gordon's son, and that this Barbara is far too young to ever be Batgirl unless the movies start skipping a decade.