I know you're probably tired of this debate, so this will (hopefully) be my last post until the next chapter is up.
If it were only about the Mokuton, Kabuto would have had access to that both with the Zetsu Obito gave him and the fact that Orochimaru must have had ample stores of Hashirama's DNA, considering his project with baby's left him enough that he felt he could sacrifice more to call back Hashirama against Hiruzen, so that arguement is inconclusive. However mentioning the Rinnegan is an interesting issue. Both the Sharingan and the Mangekyo are awakened by a mental strain rather than a physical one, so why can't the Rinnegan be one too? If that is the case, then even if the DNA was taken before the man reached that level, his soul and the knowledge that he had reached the level could be enough to allow the 'new' body to unlock the bloodlines. You're saying that the Rinnegan indicates Kabuto's control, but then what about Nagato? The man was a withered husk that had to be CARRIED for transportation, if Kabuto really had control over his summon's age, why would he call Nagato in such a useless state that even after the Uzumaki drained chakra to youthen himself he still couldn't walk, rather than just summon a younger Nagato who could still use his legs? Nagato had the Rinnegan, so having him mobile would have been a tremendous advantage for Kabuto.
Actually that raises an interesting question in itself. The Edo Tensei calls back the dead using their DNA as they were when they died, exept for Madara, with all the blemishes. The Sandaime Raikage had his scar, Nagato had the implanted eyes he died with. But Madara died with borrowed eyes, when he was last seen he had one eye and one empty socket, neither was Rinnegan or even Mangekyo-level. It's one thing to say the Edo Tensei can, or at least can be modified to, call back the summon at another age, but with Madara we're not just talking going back age, we're talking about going back TRANSPLANTS. Madara's Rinnegan weren't his eyes either, they were his brother's, and those were removed to be implanted into Nagato years, possibly decades, before Madara's death. In other words, at the time of Madara's death the man didn't have a single trace of Izuna's DNA left in his body, yet the Edo Tensei just builds back foreign parts without a blueprint? If it were the eyes he died with that's one thing, if it were his original eyes that would be another, but you're saying with just old Madara's DNA the jutsu built back organs that had a completely different DNA? I personally find it more likely that the DNA Kabuto used was of Madara when he still had his brother's eyes, perhaps it was even DNA from the last battle between Hashirama and Madara. The battle did end with Madara being stabbed after all.
Regarding the immortality-debate, sure Naruto may not want children right now, disregarding all other factors it would be a bad time for that, but are you saying with Naruto potentially living hundreds, if not thousands of years you think he'll never once want children?
And sure, the idea of living forever and having offspring is somewhat selfish, but there are far more selfish concepts. For example, the concept of one man having sexual relationshios with over thirty girls at the same time and hunting for more. Where is Naruto's karmic retribution? It's not like he found his true love, helps others find their true loves and then works together with these couples to change the world, he is honey-trapping dozens of women. That it's for a greater good and the fact the girls are happy does not change the fundamental fact that the story's whole premise is built upon a fantasy of male selfishness. So you're saying it's okay for Naruto to screw his way around the world, but if the women he does it with want more out of it than a shag, they have to be punished?
You know, your idea of 'choices need to have consequences' seems very Greek Mythology. Poseidon rapes Medusa in Athena's temple, so in retribution Medusa is turned into a monster. Let the gods, male gods in particular, do as they please, and when they're done their partner can try to pick up the pieces and pay the bill.
If your morality is Greek God, how about being consequent and have the solution to the immortality-issue be from there too? If an immortal sires a child, the immortal doesn't turn mortal, the children just don't get immortality. That would also be a reasonable price for the immortal women. You want a child? Okay, but you will have to watch it grow old and die eventually. No immortal children, no overpopulation.
You might be right with Hidan, I confess I haven't read the second fanbook, so I can't argue for or against what's written there.
So the talk hasn't happened. That was all I wanted to know.
Author's response
Madara himself said he unlocked the eyes just before he died after injecting himself with the First Hokage cells. Also Kabuto told Madara he modified him so that he came back better than when he was in his prime. I believe this means not only can the castor modify the body, but even make changes as they wish. Some might take longer than other or a certain amount of prep work might be required. There just wasn't a whole lot of reason to modify any of the other bodies. I can't imagine a young Chiyo would be a whole lot more powerful then the old one was, especially when you consider that those revived by Edo Tensei never run out of chakra or can be killed. But Madara was over a hundred years old when he died and was only kept alive artificial via the Gedo Mazo. Bringing him back at the age would likely mean he has no mobility and could easily be sealed. It made it necessary to make him younger just so he could defend himself.
I just don't understand why there is this drive that when a person can live forever he must also want to have children too. Especially when he has as you pointed out over thirty lovers he needs to please and keep happy. Also, to be honest your point about the child being mortal while keeping the mother immortal would be extremely selfish to me and not something any true mother would consider. A true father either. With that being the case I just see having a child with the gift they have been given in this story as a case of a person wanting it all and being unwilling to sacrifice anything.
About your point to true love, I don't see how the number of lovers a person has correlates to their being selfish especially when all the relationships are consensual. I mean your point about true love doesn't hold much sway, at least in my own opinion, especially since some of the characters would have to have found True Love twice. Take Tsunade for example one can say she found true love with Dan originally. Does that make her feelings for Naruto any less or more because she lost Dan? If I wrote a female centric Harem fic centered around Tsunade would that mean she loved one of them more or less then I've displayed her feelings for Naruto in this story? I believe that the answer to this would be no to both questions. Therefore how is it selfish for Naruto to have multiple lovers? The answer to me is because Society dictates that one significant other is the correct number of people we can have such "true feelings" for. I tend not to believe that love is something that can be quantified that way. Provided a person can live with their choices and they don't harm anyone else or all members participating do so willingly its really none of my business as to what they consider love or not. Therefore while you are correct in stating that this story is based on a male fantasy, I believe you are wrong in stating it is selfish by its very nature. Naruto is under no obligation to unite people with their "true loves," which if you want to go by the Naruto movies and animes alonem, he would likely be every filler female characters' true love that has appeared thus far.