Bane wasn't a puppet, he was the instigator. He even says "I am the league of shadows!" Talia may have been a big part of the plan, but I feel Bane is the one who really wanted to pull it off. He had so much respect for Ras and the league's beliefs/ideas as you could probably tell in the film.
Bane needed someone to infiltrate Wayne enterprises, by using Wayne's heart Talia was able to do so. To me, Bane WAS the mastermind behind it all. Talia was the follower, despite the last scene. I think people assume that since Talia was Ras' daughter she is automatically the leader. Who knows, to me it sounded like Bane stepped forward and took control of the LOS after Ras died, not Talia. I think Bane had the respect to take orders from her, just because of the respect he had for her father.