The original author screwed up many things, one of which is giving each sharingan a unique op ability based on the person, so he obviously killed the Uchiha clan off because he didn't want to deal with it, and the Uzumakis, Kaguyas, and other similar clans, for that matter. Same reason he killed off Shisui and gave Itachi cancer, and others like Kimimaro, and Nagato's forced crippling from using things like the Gedo mazo black rods before he even needed to.
Not going to bother reworking the eye system bullshit since it's already too integrated into the story to fix, but Itachi won't have some bullshit cancer, though he'll still have eyesight issues, so there's a good reason he leaves Sasuke alive other than gay brotherly love bullshit, but kills his parents, don't make me laugh.
A world where the story doesn't revolve around the leaf, and where the leaf isn't the end-all be-all.
Itachi Uchiha – isn't some weak jackass, but the original evil bastard villain he always was, and is meant to be, killing his clan to prove he's the strongest, the strongest assassin, and letting his little brother live only so he can collect his eyes later, and fix his blindness issue.
??? Possibly rewrite most of the bullshit, making bloodline abilities not limited to one village with so many easy ways to collect them???
???No bringing people back from the dead, the dead stay dead, and when Pain visits the leaf they reap what they sow, no get out of jail free bullshit card???
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No Kaguya/Boruto bullshit… Madara is the strongest warrior, the true endgame boss???
Whereas Harashima Senju was the strongest fool.
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??? Possibly more prevalent, very dangerous chakra beasts, possibly the main reason ninja villages were actually formed, to defend against, back before the nine legendary sentient beasts were captured and turned into jinchuriki's, thanks to help from the traitorous summoning beast clans, thus changing the world???
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MC - Uses Chakra physically, believes it to be the most cost-effective way of wielding outside of summoning. But it does require a certain amount of strength to be worthwhile.
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MC / Samui – takes her away later to start their own sanctuary village.
I think we can help each other out. You hate your breasts; I hate my dick that never goes down. So, I propose I teach/make you strong enough so that your breasts never bother you again, you'll even come to love them since they are the reason I'm doing this, in return, you help me keep my dick down, basically becoming my strong, dutiful wife.
Seeing her confused face as if asking how she'll do that, he says Don't worry, I'll teach you everything you need to know about becoming strong and being my wife.
Takes her by the hand, now come on, first I'll teach you how to be a good wife, I'll need a clear head for when I train you.
???Later – Possibly finds Tsunade and uses her addictions to lure her into bed with them and steal all they can from her???
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Subordinates
Sensor – many for village protection. – Detect white zetsu only when he surfaces, instantly killed, asked what it is, seeing the body, man says I don't know, send it to the medical unit to identify.
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Chakra absorption???
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MC has stupid amounts of chakra, which he uses as an aura cloak, making himself invincible.
Guy punches through with all his might, hitting his body for the first time, surprising everyone. He managed to do what no other could do before him, but the grins quickly faded when the MC said Impressive, I think you may have bruised me, showing his body was no less weak than his chakra… Chakra cuts off Guy's hand before he can pull it out, killing all hope within the enemy's eyes.
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Konoha? That slave state? There's no need to fear them anymore, due to infighting and weak cowardly leadership, they're nowhere near their strongest, many of their strongest having died at their ninja's own hands, leaving few left… Konoha's a joke, a nasty, disgusting joke that I'll wipe out along with the rest of this disgusting ninja society they have perpetuated with their pro slavery seals, genjutsus, and will-of-fire brainwashing bullshit. Not to mention their strongest ninjas are so weak of mind that they often kill themselves.
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Forcibly takes the three tails to protect it.
I don't need anyone's protection, least of all from a puny, weak human.
I'm sorry, I didn't realize I was talking to an idiot. Guess I'll forcibly take you for your own good since you're too stupid to survive on your own. Luckily for you, I think jinchuriki are stupid and morally wrong.
"You dare!" Eye widening when the MC chakra explodes into a massive form. "Wha, what are you?"
"The answer." Was all he heard when a gigantic chakra fist knocked him out.
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Obito, "I am Uchiha Madara."
MC, "Don't make me laugh, how stupid are you? Madara would never hide his face like a coward. It's a shame though, he's the one ninja I'd love to crush beneath my feet."