Kaoski
What if you better get a gift every time a person's destiny changes? For example: when saving Izumi, Mikoto, or some other pacifist Uchiha from dying by Itachi, Then he would receive something like resistance to illusions, an improvement in his reflexes and better vision permanently, (Without obtaining the Sharingan as that would only raise unnecessary questions about whether his mother was unfaithful to his father with an Uchiha, Better to instead just give him better vision, reflexes, and resistance to illusions passively) Another example would be that if he cures Tsunade's blood fear disease, then he could gain perfect control of her chakra. Or if he manages to prevent Hizashi Hyuga from being sacrificed for "peace" Then the protagonist could obtain the ability to be a sensor ninja and be able to sense the chakra of others from more than 1km away. In short, obtain skills related to the people whose destiny changed,
I would say that to avoid being OP, You should have a restriction where you can only get one gift each year from the person whose fate you changed in the present or the past, So if the fate of, say, Tsunade and Hinata changes in the same year, Then you could only choose one of the two to receive a gift for changing your destiny, Having to wait another year if he wants to receive the reward for having changed the other character's destiny, That is, you can choose Tsunade's gift, but you would have to wait 1 more year to claim Hinata's gift Just an idea, but something like a gift claiming cooldown time restriction might be good to avoid being OP
Kaoski:that's a good idea. But, who should I involve as there are thousands of people in the story? Are the only main ones? or the ones that have interaction with the main characters? For example, Anko, who has a connection with Orochi, Nono, who has a connection with Kabuto, and then there is Mikoto, Karin, her mother, Hizashi, etc.
Pienso lo mismo que el comentario largo( podría hacer también que cuando el mc logra enamorar a dicha chica que en el original termina con otro , recibe de regalo algo aleatorio y solo cuando el mc la enamoro completamente, recibe algo relacionado con la chica , puede ser que reciba un objeto que sirva para fortalecer su harem , y no dejarlas desprotegidas , etc.
I would prefer that you give these abilities piecemeal rather than giving them at the beginning. and has already become extremely powerful without needing any other abilities. I think the path you should follow is to find and raise your own team and talented children. I find the one man army mentality of doing everything yourself boring. You can steal Genbu, collect powerful monsters, capture the sky country (flying city) and add powerful clans such as Chinoike, Kaguya, Yuki to your team. For some reason, such stories are not written.