I have many versions of what I would change.
Most of them are too different to write. The sooner in the story you change something, more the story changes. But I will write one that I was thinking about recently.
I would make fight against Obito even longer and have Naruto and others defeat him differently. After that, Madara is revived. He does well like he did in Manga but instead of things happening the way they did, everyone faces Madara and defeat him. Or Tobirama defeats him with his attack.
Or if Madara becomes Jinchuriki, Tobirama is revealed to be the creator of 8 gates. He uses them and defeats Madara. It was hinted that maybe Tobirama created gates. At that time it was one possibility. It would make more sense that Hokage in 8 gates could fight Juubi Jinchuriki than Guy in 8 gates, in my opinion.
After that only Sasuke is left and he uses all the powers of Bijuu. Minato gives Naruto the other half of Kurama's chakra. Naruto meets Hagoromo, who would be different. Hagoromo gives him the Chakra of Bijuu he did not have. After that Naruto and Sasuke fight and Naruto wins. He becomes Hokage.
I admit, the fact that I am a fan of Naruto and Tobirama makes the story in their favor.