well yea.. negatos strong.... but i think more of wat im tryin to get at is...we shouldn't forget, that Nagato is a very strong guy! He has the Rinnegan and we also don't know what it is capable of (ok, we know that with it Nagato can see every view of each of his "dolls" and can control every Jutsu type (Fire, Earth and so on) but nothing else).
I agree with your point about Nagato -> didn't get owned by sage mode.
But then even Jiraya wasn't able to kill him in sage mode, and Kyubi didn't show us all of it's capability. (I have to mention that the chakra blast wasn't finished so that it could be some sort of "fail" and it was easy for Pain to survive it)
Hmm, the last episodes are some kind of hard to understand for me.
Ahh, a last point I'd like to say.
Maybe Naruto were able to take some control of Kyubi while training at the Frog Mountain? For me it seemed like we weren't able to see all of that what he had done up there. We also didn't know that he improved in using his Rasen Shuuriken.
(Only a prediction so far ^^ high percentage that I'm wrong but..whatever..^^)
kishi has made him so powerful, that his chakra seems unlimited....
hes been fightin since he stepped into the village...
and is now fightin the kyubbi.... seemingly with out a problem.....
i jus think thats a bit too much kinda... so in the end when we see madara fight...
the battle should be so long its tiresome... he bet not die within 2 mangas....