B. I suppose if you want to get technical it could be that, just like Jiraiya, Madara's life is incredibly difficult to revive due to the length of time he's been gone (which is far longer than Jiraiya had been dead). I don't think Obito will need a significant portion of the Juubi's strength, though... even if he were to withdraw ten times his personal chakra from the Juubi's stores, it would be a drop in the ocean compared to the power the Juubi's been throwing around.
C. That's the million-dollar question; my guess is not really. At the very least, Madara would have lost the "improvements" granted by Orochimaru's tampering with the Edo Tensei; based on what we've been shown, these essentially amount to a greater share of Hashirama's power (= Youth / Power over Rinnegan+Juubi, perhaps?). Basically, Madara SHOULD be revived in a lesser state. Worst case scenario, he's a feeble old man. Best case scenario, he's his old self, with lesser mastery of Mokuton.
D. Assuming Madara can become the Juubi's Jinchuuriki (which he always intended to be a one-person job), I see no reason why he could not follow through with the Moon's Eye Plan. There's no version of the plan that we're aware of which requires more than one Uchiha alive to carry it out. Madara only needed Obito to carry on his plans while he himself was dead. And either one of them is capable of performing the Mugen Tsukuyomi technique, since Madara showed Obito how.
E. I'm not really sure, though I'm guessing Madara has an ace up his sleeve. Maybe he'll just kill Obito out of spite and let the Juubi rampage (since Madara is the only one the Juubi cannot kill). At this point I'm willing to believe just about anything when it comes to Madara; he could use Creation of All Things (Rinnegan Izanagi...) to make himself a new body, then use some forbidden Soul Transfer technique (like Orochimaru's) to put himself in that body. Who knows. It wouldn't be that different from how he created the Zetsu and transplanted his Will into them, only he'd have gone all the way. It's pretty similar to some of our "Tobi = Advanced Zetsu Clone" theories from the days before the Obito revelation. The only issue that raises is, if Madara could do this all along, why did he bother brainwashing Obito? Why not just ditch his ageing body from the start?
F. I think Obito and Madara are looking for a way to one-up the other before the Juubi reaches that stage, or are both intended to use that stage to their personal advantage. Perhaps Obito is hoping for an opening to trap Madara in his Kamui dimension for long enough to become the Juubi Jinchuuriki and perform the technique on his own. Perhaps he hopes to in some way botch the Rinne Tensei (maybe use Human Realm to remove Madara's chakra/soul from the Edo Tensei body once Madara drops his guard). We're dealing with people who are at least aware of how to gain power over creation itself; it's possible either of them could use the incomplete Mugen Tsukuyomi, and drag the Juubi into it in the same way Obito was dragged into Madara's when it was first revealed. Perhaps if the Juubi is IN the Mugen Tsukuyomi, it can be made easier to control according to their Will, because its own power is less of a factor, and its mind would be cut off from reality and all that natural energy.
G. I think Naruto will definitely either connect with the Juubi's mind Jinchuuriki Style, or else will GIVE it a mind using the fragments given to him by all the Bijuu; I think he was given part of their individual personalities, which he could assemble into a whole and thus give the Juubi the power to resist Madara's/Obito's control.