Nice fanfic.
It was actually an Exhausted Naruto with .5 Bijuu while not having killing intent
at the conclusion of the battle. At the incipient of the battle, Naruto possessed a portion of all Tailed Beasts chakra and not very exhausted as well.
Meanwhile your precious Sasuke had killing intent that prevented him from utilizing his intelligence, Itachi's eyes, not as exhausted and had a portion of the all nine tailed beasts' chakra. If he truly utilized 8.5 tailed beasts, then they would not cease to exist... He only assimilated some of their chakra into his Susano'o to ensure that they live for a while.
Naruto's potential>/=Any Uchiha's.
OT : Jiraiya>Kakashi.
Orochimaru=Jiraiya
Let's not forget how salty both Sasuke and Kakashi were after witnessing Naruto's Rasengan.