Another plotline might be exploring Naruto's past more deeply. Maybe there are secrets about his parents that were never fully revealed in the original. In the fanfiction, he could discover something new about his father's time as Hokage or his mother's Uzumaki heritage that changes his perspective on his own powers and responsibilities.
Some fanfictions might focus on an older Naruto dealing with political intrigue in the ninja world. With his status as a hero, he would be in the middle of various power plays. He could be trying to make the ninja villages more united while also facing opposition from those who fear his power and influence. This would add a whole new layer of complexity to his character.
Maybe Naruto discovers a conspiracy within Konoha while he's in the ANBU. It could involve some of the higher - ups trying to gain more power at the expense of the village's well - being. Naruto then has to decide whether to expose it and risk his position or try to solve it quietly.
One interesting plotline could be Naruto having to deal with more complex political situations in the ninja world due to his age. Maybe he has to navigate treaties and alliances in a more hands - on way. Another could be his relationships with his friends evolving differently. For example, his bond with Sasuke might be more of an equal partnership in handling threats to the village, rather than the typical rivalry - turned - friendship we see in the canon.
One possible plotline could be that Naruto, being older, has to take on the role of mentoring Kakashi in some new form of ninja art or strategy. Since he has more experience in this fanfiction, he passes on his knowledge.
One interesting plotline could be Naruto taking on more complex diplomatic missions as he is older. He might use his charisma and newfound wisdom to bridge gaps between different ninja villages. Another could be his relationships evolving in different ways. For example, his friendship with Sasuke could lead to them collaborating on a new level of ninja research or training methods. Also, his relationship with Hinata could show a more mature side of their love, perhaps dealing with the challenges of raising a family while still being important figures in the village.
Older Naruto fanfiction often has a more nostalgic feel. It was written when the Naruto series was still fresh in people's minds, so the authors were really exploring the initial concepts and characters. Many of them focus on filling in the gaps in the original story, like Naruto's early years or what happened between certain arcs. They also tend to be more influenced by the early art style and themes of the anime.
One common theme is the passing of the torch. Older Naruto is often shown mentoring the younger generation, like how Kakashi mentored him. Another theme is dealing with the scars of past battles, both physical and mental.
In fanfiction, an older Naruto may have a more refined sense of leadership. He has seen more, experienced more battles and political situations. So, he might be more diplomatic in his approach compared to his younger self.
In such fanfictions, the plot might revolve around them teaming up for a mission. Maybe it's a mission that requires Naruto's brute strength and Hanabi's precision and knowledge of the Hyuga techniques. This could lead to them growing closer as they face challenges together. Their interactions during the mission, like Naruto making Hanabi laugh with his silly antics or Hanabi impressing Naruto with her skills, would be interesting to explore.
A popular one is 'Naruto: The Next Generation'. This fanfiction focuses on the new generation of ninja in Konoha, but still has Naruto playing an important role as a mentor. It's interesting to see how the new characters interact with the older, more established ones like Naruto.
The older brother in the fanfiction might be a character with a tragic past. For example, he could have been experimented on by Orochimaru and gained some strange powers as a result. And he returns to the village later to protect Naruto from the threats that are coming towards him.