Marion Cotillard will play Talia al Ghul, and the scenes featuring Pence will actually be her memories of her father (and in a fresh way of doing things, there won't be a child actor in the role of Talia - because they are her memories, the adult Talia would appear in them to show them from her perspective). In BEGINS, Ra's says that he once had a wife and daughter, and that they were "taken from him". I'm willing to bet that we'll see some of that, and that he will be considerably less innocent in the whole affair than he made out (people, after all, have a way of remembering things with them as the victim, even - and especially so - when they are at fault).
Talia won't actually be in the League of Shadows. Indeed, she will have no idea that they even exist. But while Batman is off in hiding, she starts seeing a psychiatrist, Hugo Strange, who starts digging up her memories. He may also appear in these flashbacks, observing alongside Talia. Ostensibly, he is trying to help her. In reality, he is trying to find the League and use them to flush Batman out. he plays on Talia's childhood memories, prompting her to see out the League of Shadows. The remnants of the League rally to her as she is Ra's daughter, and with Strange as their "advisor", they head to Gotham.
Somewhere along the way, they find Bane. He would be a creation of Strange and Talia, a brute who was trained by the League and set loose on the streets as "Batman". Strange is trying to prove that anyone can be Batman; it's just a question of circumstance. The whole film would be pitched backwards, with Bane as the initial threat, ultiamtely revealed to be a puppet of Strange and Talia. Talia's memories would show that her father was never a hypocrite and was only trying to do right by her (and ultimately succeeding). But because at least one character in each Nolan film is essentially a tragic figure, she would never get the opportunity to reconcile her memories, as Strange would have long since corrupted them.