Some important thing are that: This is a Au. Not cannon. Things will be different, a lot of things.
I'll have the standard Naruto power system shown in the manga but more explored. As for Kaguya+Other otsutsuki , I like the idea of them but they probably will come much later in the story. Aka Madara won't be manipulated and stabbed by Black zetsu. If I see a comment complaining this or that didn't happen in cannon. I will violently have a seizure.
Our reincarnator will not be the main focus. Other characters will be explored and even have their own chapters/arc dedicated to them.
Speaking of focus, it'll be on 4 people. As in the standard squad with a Sensei and three students. Keep in mind this includes a girl. Which is something I've noticed that not many people like having a female main character. If you're one those people then you should probably read something else.
But like I said side character/characters that are important in Naruto. I good example will be Fugaku Uchiha. You'll be reading about him for now because I'm not writing the reincarnater being a baby. That's boring. Nobody like that.
And probably the most important thing is that Jimmu, the reincarnater power will fluctuate. He does get advantages being a reincarnater, don't worry about that but it won't be a system. Let me be clear about that, no system in this.
I'll do polls or ask in the comments on what do you want Jimmu doing. Or if event a is better than event B. So you guys will have a say in this story.
I can promise this, I will not drop this. I've invested a unhealthy amount of time looking over at recons in og cannon, the power system of Naruto, why the women in Naruto suck and nobody like likes them. Stuff like that.