Naruto would be more disciplined. Gai's strict training regime would make him more focused on his goals.
His character would develop a strong sense of loyalty towards Gai. Since Gai is all about passion and determination, Naruto would also show these traits more prominently. He would be less likely to give up in difficult situations and would have a more positive outlook on life, similar to Gai's 'youth' concept.
In this fanfiction, Naruto's development would be quite different. With Gai as his mentor, Naruto would learn to value hard work and self - discipline above all else. His social skills might also be different as he would be more influenced by Gai's straightforward and energetic nature. He would be more likely to take on challenges head - on, without hesitation. His ninja skills would be more physically - based, like Gai's, and he would be known for his powerful taijutsu. His growth would be centered around becoming a strong and honorable ninja, much like Gai himself.
His character might be more hardened. Growing up with Yahiko, he'd be exposed to the harsher side of the ninja world earlier. So he'd be less likely to trust blindly.
Naruto's character would likely be more distrustful of traditional ninja institutions. Since he's raised by a rogue, he might see the established ninja villages as corrupt or overly restrictive. He could be more rebellious and less likely to follow orders blindly.
Naruto might become more sensitive and perceptive. Since kunoichi often have a different way of looking at things compared to male ninjas, Naruto could pick up on those traits.
Naruto's view of family would be different if raised by Pakura. Since Pakura could be seen as a surrogate mother figure, he'd have a different understanding of maternal love. This would affect his relationships with others, especially female characters. He might be more respectful towards women from the start. His growth as a ninja would be more centered around Suna's way of life. For example, he'd be more involved in protecting Suna's trade routes and resources, which would shape his ninja skills and values in a way that's distinct from his Konoha - raised self.
Naruto would probably be more in touch with nature. Since slugs are associated with earth and natural elements, he might have a calmer and more patient side to him.
Naruto's character would likely become more brooding. Sephiroth's influence could make Naruto more introspective and less likely to wear his heart on his sleeve. He might develop a colder exterior to match Sephiroth's aloofness.
His character would develop with a stronger sense of loyalty towards Jiraiya. He would inherit Jiraiya's values like protecting the weak and seeking justice. Naruto would also be more well - versed in the ninja arts and history due to Jiraiya's teachings. This would make him more respected among his peers at an earlier stage. Moreover, he might be more patient and less impulsive as Jiraiya could teach him the importance of thinking before acting.
Naruto's character would likely become more reserved in some ways. Yamato is not as boisterous as some of Naruto's other influences, so Naruto might think before he acts more often. His fighting style could also be more strategic, incorporating Yamato's wood - style and knowledge of chakra control.
In this fanfiction, Naruto's character development would be complex. Growing up with a Jinchuuriki, he would have a deeper understanding of the power within. He might not be as loud and brash as in the original. Instead, he could be more of a silent observer at first. As he grows, he would gradually show his leadership skills in a different way. He would use his knowledge of the Jinchuuriki and their power to inspire others, and also be more diplomatic in dealing with different clans and villages, as he has seen the consequences of being an outcast through the Jinchuuriki's experience.
He might become more stoic. Given the nature of Shinigamis, Naruto could grow up with a sense of calmness and detachment that's not typical in the original Naruto.