Re: Contrasts between Bane and Ra's
Magnar points out a very pertinent aspect, that Bane is an amalgam of villains, as well as a dark mirror to Bruce Wayne himself.
The parallels with Ra's, as well as the clear distinctions between the characters have been covered eloquently and in great detail by BatLobster and Mr. Wooden Alligator. Taking the amalgam aspect into mind, it would've been impossible to view Bane as Ra's II anyway. Bane is also similar to the Joker in that he seeks to give the people direct control of their destinies, so that he can prove that Bruce's faith in them is unfounded. There's also a consistent nuance of LoS ideology into that line of thought as well, namely with wanting to set an example to the world through Gotham's destruction.
Essentially, it's a variation of the "When the chips are down, these uh, these civilised people, they'll eat each other" viewpoint. It's actually a staple of all of Batman's villains, they want to show him just how pointless his crusade is.