The main villain is one of the weakest parts of TDKR. More unintentionally funny than intimidating, with a plan that makes no sense at all and a really underwhelming death. And then suddenly it turned out that he's never been the main villain at all.
Bane and Talia were the main villains, though Bane had the stronger story. His past, a mirror to Bruce's own, ultimately gives Bane the deepest relationship with Bruce out of all the villains in the Dark Knight Trilogy. The plan itself made plenty of sense if you think about it: Bane's doing what Ra's failed to do, and to greater effect that if Ra's had succeeded. Ra's plan hinged on a drugged populace destroying Gotham. In contrast, Bane simply laid bare the truth behind Harvey Dent and gave the Gothamites the tools to exact revenge. All with constant news coverage, so that the world could see a perfectly sober people devouring their own--eating each other when the chips are down.
Aside from succeeding moreso than his father figure, Bane is a symbol of who Bruce could have become if he'd fully embraced the League's philosophy. Recall Bruce's original intent with the Batman persona: shake Gotham out of its apathy, encouraging Her people to take back their city from a bureacracy that, for the most part, was controlled by Falcone and other mob bosses. In The Dark Knight Rises, we see a very similar situation: a city where the mob element has been virtually eradicated, yet there's still deep-rooted corruption in the city's government. The source of that corruption is the lie Batman and Gordon agreed on in The Dark Knight. The fruit of their duplicity, the Dent Act, unjustly gave the police the authority necessary to finish off a weakened mob. So, if you remove yourself from the notion of "good" and "evil", and look at things in terms of "Order" and "Chaos", a rotten form of Order--the Dent Act-- overthrew the Chaotic elements within Gotham's government, the mob bosses' influence. Cue Bane.
Bane arrives and finds the tools he needs to expose the rotten Justice that has been brought in the form of the Dent Act. This wasn't Bane's stated intent, however. Recall, prior to learning of the Dent Act, he had been taking in the at risk orphans and others who were having trouble finding work in Gotham. Gordon's confession was extra ammunition for Bane's goal of proving himself the worthy successor to the League of Shadows. By giving the poor the means to fight back against the wealthy, and exposing the Dent Act for a fraud, Bane manages to accomplish what Bruce set out to do as the Batman: inspire the citizens to retake their city from the corrupt elements.
Talia's role was much smaller; she served two purposes: a way to create a sympathetic backstory for Bane, and symbol of what Bruce could've become if he had obsessed over his parents' death. Given that she's the grandchild of the Warlord who imprisoned them, and their anger toward the Warlord, it isn't hard to imagine what would've realistically happened to Talia if Bane hadn't intervened. Similar to Bruce with his parents, she became fixated on her father after his death. Bruce wanted to attack the elements that contributed to their death, ultimately. In contrast, Talia wanted to go after the murderer. Recall in Batman Begins, that Bruce restrained himself from killing his parents' murderer. Thus Talia worked to strengthen Bane's backstory and symbolize Bruce's fate if he had decided to simply seek vengeance.
Thus, the main villains' plan does make sense, and they are half of TDKR's strength. The other half being Bruce's arc. I can't say anything about that voice, though.
t: (Also, this is my reason for ranking TDKR as my favorite in the trilogy, with TDK and BB tied; their place in the hierarchy depends on my mood).
