This is interesting. So it is seems he doesn't need all of the chakra from the bijuus, as long as he has at least some of it. I think Madara will succeed in his plan, but the chakra at his disposal won't be enough to counter Killer Bee and Naruto. They will remain unaffected by the Moon genjutsu, possibly having to fight the remaining shinobi army and Akatsuki. Similarly, Sasuke due to his MS, or now EMS, will be able to survive the genjutsu cast by Madara.

In fact, it may transpire that Bee is left to deal with the combined remainder of the Shinobi and Akatsuki armies, whilst Naruto and Sasuke fight it out before a watching Madara. Whoever wins, will ultimately have to yield to what Madara is saying and I don't see either Naruto or Sasuke doing that, leading to a confrontation with Madara. Madara may be too powerful for the exhausted winner to take on, but at this point Kabutoro will enter the fray and complicate matters for Madara.