It would make him more self - aware. By letting go of Sakura, Naruto is forced to look inward and understand his own emotions better. He becomes more in tune with what he really wants in a relationship and in life.
This adoption could have a huge impact on Naruto's character. He might become more introspective. Since Kakashi is a complex character, Naruto could start to think more deeply about his actions and the world around him. He may also become more reserved as he tries to live up to Kakashi's expectations, but at the same time, he'd still keep his core, energetic self.
Naruto's character would likely become more complex. Danzo's training methods are strict and often involve a certain ruthlessness. Naruto, used to more open - minded and friendly training from the likes of Jiraiya, would have to adapt. He might become more calculating and less impulsive, which could be both good and bad. Good in that he'd be a more strategic fighter, but bad in that he might lose some of his charm and spontaneity that his friends love him for.
The cloak could make Naruto more confident. If it has special powers, he would feel more capable and in control. For example, if it gives him the power of invisibility, he might start to take more risks in battles and become bolder in his strategies.
In many Naruto fanfictions, Naruto letting go of Sakura can lead to some interesting character developments. It might be because he realizes his feelings for her are more of a childhood crush and he discovers new relationships or focuses more on his ninja goals. For example, he could start to see Hinata in a new light and pursue a relationship with her instead.
He could gain a new sense of pride in his heritage. Since the Uchiha are known for their power, Naruto might feel a stronger drive to prove himself worthy of his mother's bloodline. This could lead to him training even harder and achieving new levels of power more quickly. For example, he might develop a unique fighting style that combines Uzumaki and Uchiha techniques.
The relationship with a sibling could have a huge impact on Naruto. If the sibling was older and more confident, Naruto might look up to them and learn from their example. He could become more disciplined and less of a troublemaker. On the other hand, if the sibling was younger, Naruto would feel a sense of responsibility, which could mature him faster.
It could have a mixed effect. Some fans might love it as it adds a new and different perspective to the Naruto - Sakura relationship. They would enjoy seeing how the harem concept is incorporated into the Naruto universe. Others might be against it as they prefer the more traditional relationships shown in the original series. For example, purist fans might think that the harem idea goes against the essence of Naruto's character which is mainly about his journey to become Hokage and his friendship with Sasuke.
If Zabuza found Naruto, it could make Naruto more independent. Zabuza is a loner, and Naruto might pick up on some of his self - reliance. Naruto may also become more in tune with his darker emotions. Zabuza has a lot of anger and pain inside him, and being around him could force Naruto to confront his own inner demons. This would add depth to Naruto's character, as he would have to learn to control and use these emotions in a positive way, rather than just relying on his positive - thinking - only attitude all the time.
Itachi's influence would make Naruto more empathetic towards the Uchiha clan. He would understand their side of the story better. This would change his approach to dealing with the conflicts related to the Uchiha. Also, Naruto would be more skilled in stealth and strategy. Itachi's training would focus on these aspects, and Naruto would develop into a more well - rounded ninja, with both power and finesse.
Well, the experiments might initially make Naruto question his own identity. He might wonder if he's still the same Naruto after all the changes Orochimaru has made to him. But in the long run, it could lead to a more mature Naruto. He might start to view his power and purpose in a new light. He could become more self - reliant, not just relying on the Nine - Tails' power but also on his own newfound abilities from the experiments, and use them for the greater good.