I would like to start by saying Hello, this is my first time posting on this site. I'd like to share one of my Danzou theories that is relatively messy in terms of order but bare with me, tell me what you think.
Part one of my theory
My theory with Danzou is that after Itachi left and joined Akatsuki, Danzou made a deal with Orochimaru to wage war on the Hidden Leaf using the Suna so that Orochimaru could kill the 3rd for him since he pledged that he would protect Sasuke to Itachi. So when the 3rd hokage died, Itachi came back to the Hidden Leaf to show Danzou and the other Elders (who probably had roles in this as well) that he is alive and Sasuke still have a protector, but not only a protector but a real Sharingan user. After this, Danozu really didn't have any chance to assassinate Sasuke in some way because he left the village soon after and went to Orochimaru. Which three things happened at this point:
Orochimaru: Things are going according to plan for him because hes got his new vessel.
Itachi: Things are going fine for him because he have 2 and a half years before Orochimaru can try anything, and he most likely knew Sasuke wouldn't let him take his body.
Danzou: This wasn't part of the plan, which is why he sent Sai to assassinate Sasuke before Orochimaru could get the body, the note Sai gave Orochimaru most likely mentioned the name Danzou which is why he allowed him to even enter his hideout.
Sai's missionwas unsuccessful, but now the events now that are currently happening are helping Danzou's side in this story once again. At this point he is trying to erase anyone that had any knowing of the dealings with Orochimaru that he has made in the past by killing Kabuto and Anko.
Part two of my theory above
Starting to think about back when Tobi said "My powers, Uchiha Madara's powers", I' wondering why would he talk in third person? Maybe there is a person that is controlling Tobi's body (in this case im speculating Danzou via Shishui's jutsu) is planning on using his powers with
Madara's powers. Which is probably why he wants Sasuke to get so strong so that he can gain a second Sharingan with the powers of a uchiha of the level of Madara. It may be that Danzou is using this "Tobi" character to get what he wants and stay hidden.
Another Theory regarding Nagato this time. In the past when Danzou and Hanzou teamed up to kill Nagato, Yahiko and Konan, had plan was to kill Nagato so that he wouldn't have any competition when he had his plans complete. But since he became leader of Akatsuki, he decided to use him and at the same time kill him. He did this by sending him on a blind mission to capture Naruto in which he hoped he would be killed but at the same time not prevail at his mission and kill Tsunade. Though he didn't kill Tsunade, he did the next best thing put her in a coma. After this, Nagato tells Naruto that he doesn't trust Tobi and he must be stopped. Which deep down he felt suspecious of him.
If you ask me, if this is all true in my theory, everything is going according to plan. And theres actually 1 true villain in this series and I probably have to give Kishimoto some credit with this one.