Not underestimating Naruto here (However Sasuke gets under-rated the most in narutobase), Naruto is an absolute powerhouse, but in terms of flexibility and versatility he really lacks in that aspect. Having more jutsu's in his belt will take his flexibility and versatility to the next level.
Naruto is certainly stronger than Kakashi and Sasuke. When it comes to flexibility and verstality they would absolutely beat him in that aspect. Kakashi utilizes a lot of ninja tools, knows vast amounts of jutsu's and uses his intelligence well in bad situations his in at times. Sasuke has two elements under his belt and knows how to perform an array of jutsu's. That's a reason why Naruto will struggle to defeat him, fanboys would think it'd a be one-shot rasengen that can take on him. Think again, Sasuke is really stong (he has acquired the EMS, which is just a step-away getting the Rinnegan), they can easily be a turn of event where he might eventually beat Naruto. Also for Kakashi is ahead of me Naruto in that aspect, theirs a reason why the elders and fire lord almost choosed Kakashi to become the new Hokage.
Well, what sucks about it from Part I was his chakra and was mixed with Kurama chakra and I can see how he had trouble learning jutsu's at that time. Part II (Time-Skip) I imagine he should've learnt more.
It'd make sense, if he went off somewhere after the Ten Tail Arc and learns more jutsu's. Just my opinion... Rasengan and Kage no bushin are great (being able to perform rasengan with one hand would be a lot better), but having more jutsu's is better which will add to his flexibility and versatility. So it can fully ensure Naruto defeating Sasuke (without killing him) and becoming the strongest hokage ever lived.
and orochi was only seeing what Naruto had and said "you still don't compare to sasuke." Also at the final valley sasuke started up and he was beating naruto up. He always starts with Naruto first.
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