I think Madara's history, well probably here the story surronding him, Nagato, and Tobi from Tobi and the story surronding Hashi and Madara from the 9 tails. Madara has served his purpose and you all are forgetting that he isn't even in his actual body he is using someone else's. Neither Izanagi or Rinne Rebirth would work in this situation. I think he has served his purpose, we will probably see more in flashbacks with the 9 tails and Tobi.
As for the Kage's maybe you have forgotten but there exahausted and they just got beaten badly. Fact is they lost he fight, if it wasn't for Itachi they would be dead. I think that is going to hit them hard.
Madara probably uses his final moments to mock them and point this out to them. I firmly believe that somewhere along the line Naruto is going to have to step up to the leadership plate during this war. Something is going to put the Kage's out of commission and Naruto is going to have to pull the army together. Because I doubt Tobi was stupid enough to go into this war without several back up plans.