The plot itself was actually kind of interesting. Focusing on Hagoromo's brother Hamura and his descendants was actually kind of neat. I still don't really have any idea how/why the Byakugan gang was involved though. Were they descendants of the Hamura side? Whatever happened to the Byakugan being a genetic mutation from the Sharingan? lol. And I chuckled when the Tenseigan ended up being a "Golden Byakugan", albeit, I don't remember if that joke was from this forum or a different one I visit.
The major downside was all the fighting plotkai. Sasuke shows up for like 3 seconds and you can clearly see he has his Sharingan+Rinnegan combo going. But Naruto doesn't really ever go all out. At least, not in his SotSP mode. He does go Kurama+Sage mode when it counts, but for good chunks of the movie I was just like "/sigh... stop fucking around and just go all out already."
Also, don't know if it was movie plotkai or what, but don't recall Kurama being able to ever leave/fight freely outside of Naruto's body. Albeit, I could buy into it being a new ability/side effect/whatever as a result of the end of the manga. That part actually could make some sense and is actually pretty reasonable. Kurama freely storing himself/supplying his chakra to Naruto out of free will as opposed to being sealed inside him and thus being able to leave whenever/if ever the situation called for it, while still leaving Naruto with some of his charka.