Obviously, the new Hokage would be one of the main characters. It could be a character we already know like Naruto's son, who has inherited his father's determination and strength.
Shikamaru is another possibility. He is known for his strategic mind. As Hokage, he could use his intelligence to make wise decisions for the village. He may not have the brute strength of Naruto or Sasuke, but his ability to plan and analyze situations would be invaluable in leading Konoha.
Maybe the new Hokage is faced with a crisis within the village. For example, there is a rift between different ninja clans, and the Hokage has to use his/her diplomatic skills to bring peace. They could start by holding clan meetings and listening to each clan's concerns.
Perhaps a perk is the ability to shape the future of the ninja world. As Hokage, one can inspire the younger generation of ninjas. They can create new ninja academies or training programs. They also have the power to pardon or punish ninjas according to their deeds, which helps in maintaining law and order in the village.
Sasuke could also be a possibility for the 6th Hokage in the fanfic. He has grown stronger over the years and his unique perspective on the ninja world could bring new ideas to the leadership of the Hidden Leaf. He might start off as a controversial choice but prove himself through his actions in protecting the village and making tough decisions.
A really interesting plot could be Naruto traveling back in time to the era before he was born. He could meet his parents and other important figures in the village's history. This would give him a chance to understand the roots of the village better and also learn some new jutsu or strategies that he could bring back to his own time to make the Hidden Leaf even stronger as a Hokage.
I really like 'Naruto: Hokage's Ascent'. It delves deep into the political aspects of being Hokage, which is not often explored in great detail in regular Naruto stories. It shows Naruto having to make tough decisions for the village, and the relationships between the different ninja clans are also well - portrayed.
One possible fanfic could be about the 5th Hokage, Tsunade, facing a new and powerful enemy that the village has never seen before. This enemy could be a rogue ninja from a far - off land who has a special jutsu that can disrupt the chakra flow in the village. Tsunade would have to use her medical ninjutsu and combat skills to counter this threat and protect the village.
Yes, there are likely many fanfics with that theme. The Naruto fandom is huge and creative, so it's common to find fan - made stories exploring different 'what - if' scenarios, like Naruto becoming the fifth Hokage. You can look for them on popular fanfic websites.
Sasuke could also be a candidate in some fanfics. He has his own set of powerful abilities and a complex personality. A story could be written where he decides to take on the role of Hokage at a young age to bring about change in the village in his own way, perhaps using his Sharingan and new techniques he develops.