In any case we already had this figured out lol it's so obvious the more you look at it really is the only thing that makes sense.
After Izuna gave up his eyes he probably started killing other Uchiha to find the "right eyes" for him. I think like Orochimaru he may have become a little unhinged and obsessed with this pursuit. He may have experimented with people both Uchiha and other clans to find a way to restore his power or improve it.
- Its possible that this obsession may have made him a bit of a nuisance to both sides. I wonder if the 1st Hokage's death is tied to Izuna?
- The forbidden jutsu he has prepared is probably a variation of the Creation of All Things jutsu that can restore his body to full power.
- I bet Itachi is the one who told some of the other members of Akatsuki about Izuna
- I think the idea I had in my mind from before is the correct one & The Eye of the Moon plan is only step 1 in Tobi's plan. What he really wants is to use the Creation of All things Jutsu then he can literally alter reality into anything he wants not just some Genjutsu. He will be able to alter all living things into a new form perhaps even absorb them into himself and become some kind of god like being powered by the Jyuubi.
Also he was another Kishi interview that predated this I guess:
Question: The legendary shinobi is now immortal! Does Uchiha Madara have any weak point?
Kishi: All strong people have some kind of weak point, but Madara does not. How will the fight from here on out go!? Please stay excited and wait to find out!!
Question: I’m curious about the connection between Madara and Tobi!
Kishi: I obviously can’t give too many details, but the two do know each other. What kind of relation they have will be gradually revealed in the current story!!
Question: Will Tobi’s identity be revealed soon…!?
Kishi: Indeed it will. In fact, it should be within the next few weeks!! Everyone, please wait and keep predicting until then!!
Question: How will Naruto and Sasuke’s story proceed now?
Kishi: I think that they will meet up once again during this war. Please look forward to seeing what will happen then!
Question: Now that we’ve entered the climax of the Great Shinobi World War arc, please tell us what some upcoming highlights will be!
Kishi: Everything from here on out will be a highlight!! Everything’s just going to get more and more exciting!! Everyone’s favorite characters will gather together to play a big part!! Please continue enjoying Naruto now that the Great Shinobi World War is in its climax!