Bane was my favorite hero of the trilogy. And if you disagree, well then I guess that's IYHO.
By trying to complete Ra's work and for saving Talia from death, I feel that he was a hero. Anyone who helps a small child escape certain death and escape from a pit of a prison is a hero in my eyes. PERIOD.
And even if you disagree with what he did later with his life, look at Harvey Dent. He turned evil too. Yet there's no Bane option to choose despite his heroism.
HE HAD TO WEAR A PERMANENT BREATHING TREATMENT BECAUSE HE SAVED A LITTLE GIRL! That, my friends is a hero.