The rinnogans true power, isn't really anything, just the ability to use any jutsu. and that's it. the 6 bodies of pain arn't even actually apart of the kekkei genkai, it is just a jutsu that nagato(hypotheticely the real pain) could learn because of those eyes, but not apart of those eyes. the jutsu like in the last manga told us is just similer to the yamanaka's secret clans technique, which allows them to be linked and see the same stuff, but it is not the actual rinnogans technique.