even if the shinobi defeated madra, if it wasn't for naruto's personality they wouldn't have a future. the first hokage followed on naruto's footsteps and shared his memories of a "dream of the future" with all the shinobi, that was the end of hatred and the beginning of a true trust, that was the climax of naruto's development.
the reincarnation happened far later after the shinobi truly united, and it was only to defeat madara, because his existence as a common enemy was no longer necessary, and it was a chance for the sage of the six paths to redeems his past mistakes by equally granting power to both his sons' reincarnations, he even knew naruto & sasuke's answers before he gave them power, knew that sasuke won't seek peace and still granted them the six paths.
at the end it all came down to naruto's personality.