I think your 4th point is wrong, coz he can't control bijuus with sharingan, he can only control them using rinnegan, all the jinchrks and tobi are connected with one another via rinnegan and proof of that is a rod at chest, and thats why kakashi said that why all the jinchrks are not using the 6 paths of pein tecniques? And then he also said that because of controlling 6 bijuus at a time is more than enough, which takes almost all chakra leaving not enough chakra for using those techs..
and btw nicely done xd
and btw nicely done xd
