1.rinnengan is needed to summon the Mazo, Senju DNA gives you the ability to utilize it.
2. Obito probably used Madara's will as a converter to use the 6 paths technique. It contains Madara's (a Rinnengan user's) chakra condensed this allows Obito to use Madara's jutsu.
3. Naruto was able to show his memories to everyone because Ino acts like a server. She can connect everyone's mind . This connection of course done through chakra. Naruto's chakra and feelings were just so strong that the images could be relayed through ino's jutsu.
4. Even Minato saw Obito's memories, however Naruto had links from beasts 2-7 as well as 9 so he had a much better connection one strong enough to interface with Obito's mind.
5. Anyone can create pressure through chakra, Hashirama did it, Orochimaru, and even Hiruzen did it. Bijuu have excessively strong chakra so if they did the same it would be much greater (like Naruto's )
6. Everyone can give or exchange chakra
7. Kurama doesn't know any of the 6 paths jutsu except the ones he experienced. When he broke out of CT that was pure rampage. The Sage only told the bijuu aspects of the prophecy.
Sorry, I appreciate how much work you did for this thread, but I am 100% against the notion of a Naruto getting the Rinnengan and/or becoming the juubi Jin. I am pretty sure I had more qualms than these, but were the main ones that stuck out.