Reread my post.
Naruto would've failed without Kurama. Even Minato believed that Naruto needed to tame Kurama's power in order to become the true savior. It was because of Kurama's power that Naruto felt the need that he could fight Sasuke, it was because of Kurama's power that he managed to prove Raikage that he was the savior, and it was because of Kurama's power that Minato felt confident that Naruto could fight Obito.
Kurama isn't as much of a part of Naruto as the Sharingan is to Sasuke because Kurama isn't something inherited through your bloodline. The Sharingan is a natural part of an Uchiha's power whereas the same shouldn't apply to Kurama who acts as an additional power outside of a Senju/ Uzamaki's bloodline. The Sharingan is the equivalent of the massive Lifeforce obtained from being a Senju/ Uzamaki, Kurama just acts as an additional power source.
And as stated before, without Kurama, Naruto wouldn't have been able to convince Nagato that his path was wrong because he would've been captured by Pain, hell, he would've been killed off by Sasuke at the VoTE.