Danzou I suppose was a little redeeming in the end, but I still regard him as a bastard.
When they were kids, Hiruzen was a kind and selfless guy who put his comrades first, including Danzou while Danzou was rude, selfish, arrogant and jealous of Hiruzen. They had a real Kain and Abel existence and relationship.
I got the feeling that just because Tobirama chose Hiruzen over him, Danzou developed disdain for him and everyone else to the point of rejecting and rebelling against Hiruzen.
Hiruzen was brave, used his own power, brought a sixty year peace to Konoha and worked to get where he was before finally giving his life to save everyone.
Danzou protected the village with his anbu for a while, but was cowardly, viciously deceived Hiruzen, worked with Oorchimaru to overthrow the village and killed dozens, let Pein destroy the whole village and all its people simply because he hated Tsunade and the hokages' ideals and principles, looked for no solution to stop the Uchiha other than killing them and stole power from both them and Hashirama rather than relying on his own. I will admit he was a good antagonist, but he was no saint or savior like he believed he was or wanted to be. If you truly care about the people, you don't ruthlessly slaughter them or let them all die just because you reject their ideals. That's hypocrisy and wickedness at it's finest level.
Again, he repented a slight bit by trying to kill Obito with his Kamakaze jutsu and wanting to fight Akatsuki rather than joining them, but at the end of the day, he knew deep down in his heart that his soul was too heavy with sin and that he could never be Hiruzen or go to where he went.