if u watch d video minato said it would be un wise to seal something with this much chakra into a baby.so he had to remove some so that he can seal it in naruto.naruto still a baby wouldnt enough chakra to keep something dat large so removing de chakra was basically to weaking kurama for dat...
I strongly think that naruto should learn the sage mode too the last.and a complete new technique so that he can use many jutsu like his father.anyway dat is my opinion.wats yours.:shrug:
i know naruto to be around 16 years of age (due to his mothers speech to him when trying to tame the nine tails).secondly naruto,sasuke,shikamaru,etc should be around the same age bracket.so how old can hinata be.