Naruto might be strong and powerful now, but he is hardly the strongest or most dangerous.
For starters, Naruto has no defense against a decent genjutsu. It is his biggest achilles heel, and the Sasuke hasn't killed him already by using it is because he wanted to prove Naruto was simply weaker than him. Unless the Kyuubi actually helps out when he is under an illusion, Naruto is rightly screwed.
That means that pregnant what's-her-face could take Naruto down right now. As Kabuto is a skilled genjutsu practitioner he could defeat Naruto as well. All of the Sharingan users could.
Naruto would also have a hard time against Sasori, because even being scratched is a slow, agonizing death, and Naruto isn't exactly known for being hard to hit. He is more like a slugger than a surgeon. Naruto can make a 100+ clones, but Sasori's chakra threads might be able to control them as well.
Naruto would have been massacred against the 3rd Raikage had he not figured out how to defeat him. In a match of power vs power, he didn't stand a chance.
I can't see Naruto defeating the insidious abilities of the Kage of the hidden Mist either. Her abilities could dissolve him before he could do anything about it. Even Susanoo couldn't protect Sasuke from her.
And to be perfectly honest, I don't think he is skilled enough to defeat his dad, who could teleport instantly behind him, and teleport powerful attacks away. His dad could also create a seal on the fly that would cause Naruto to lose the ability to use the Kyubi.
And if Diedara used his final explosion, how would Naruto survive, though that would be a Pyrrhic victory.
Heck, Hidan could beat Naruto if he can get a small scratch in. Let Naruto rasengan himself out.
Heck, I'm almost certain that Danzo could have done him in relatively easy, but I have a suspicion that the cells from the 1st hokage react negatively to Naruto's current kyubi chakra. I suspect that is why Tobi couldn't simply pass through him.
And lastly, I'm pretty sure that Killer Bee could beat the snot out of Naruto, if for no other reason than experience.