well he wouldn't be fine if he didn't know genjutsu or how to properlly dispell it cuz if he fights pein or sasuke or madara im pretty sure each one of them can cast a extremelly powerful genjutsu we already know sasuke can pein has the most powerful eyes so i know he has to do something there...
i think that would be inculded with strength but what he needs the most training in is genjutsu man all sharingan users do is mostly genjustu well the beginning of the fight
wait i take my message back cuz naruto can summon like 1000clones and since that can speed up training like one day with a thousand clones can probally equal a year cuz if one clone learns something he'll distrubute it the the toher clones and the real one idk but yea naruto will surpass him he...