Scenario 1: Naruto wins mid-high diff. Only because it's an IC fight. This being War Arc SM Naruto, he has access to way more KB and we saw "in-character" that Naruto used Rasenrengan, FRS and Frog Kumite from the get go against Pain. Therefore Pain will get overwhelmed by Naruto's attacks before deva is able to shell out CT. Plus, if this is untrue and Pain is able to use CT, Naruto is now friendly with Kurama enabling him to use Frog Song, which I believe with all those KB, will allow for the proper preparation.
Scenario 2: This is a toss up. If there are civilians around like before then Pain wins high diff. If not, Naruto wins high diff. That's because with full intel, Naruto could just distract the paths with multiple SM KB, retrieve a chakra rod from a dead path, and go after a weak Nagato with enhanced SM sensing, killing off all the paths at once. In the other case, Naruto wouldn't leave the civilians in peril, so he'd have to take care of every path, and their knowledge of him having frog kumite and FRS would be a detriment to Naruto's cause. Pain would also intend to kill Ma and Pa as he knows that would be Naruto's most devastating attack. KB would still cause trouble for Pain though.
Scenario 3: BM Naruto has to take it I feel. TBB will obliterate any CT attack. KB will give the other paths a run for their money.
