Well, in some fanfictions, Naruto might be promoted over Sasuke because Naruto has always been seen as the more positive and inspiring character. He has a strong will to protect his friends and the village, and his growth throughout the series is more in line with the traditional hero's journey. His ability to make friends and bring people together could be a reason for his promotion in the fanfiction.
A great fanfiction idea for Naruto's Chunin promotion could be that Naruto has to face an unexpected enemy during the exams. This enemy tests his limits and forces him to dig deep into his newfound powers. Along the way, he also has to deal with the politics within the ninja village. His success in both combat and handling the village politics is what results in his promotion to Chunin.
In the 'naruto wants to be promoted' fanfic, Naruto may struggle with the traditional ways of the village. His unique approach to being a ninja, which often involves thinking outside the box, might not be fully understood or accepted by the old - school ninja leaders. This lack of understanding could lead to resistance against his promotion. Additionally, he may have to deal with false accusations. Some might spread rumors about him to prevent his rise in rank, and he'll have to prove his innocence and worthiness for promotion.
In a fanfiction where Naruto is promoted to chunin, he might immediately start taking on more challenging missions. He could be put in charge of a team, leading his peers and showing off his newfound leadership skills.
Naruto could also be tasked with training a new generation of ninja. Since he has his own unique style of fighting and a lot of experience, he would be a great mentor. He might teach them his signature rasengan or how to better control their chakra.
Often, Naruto is shown to be the one who trains new generations of ninja more effectively. He might be promoted to a high - ranking teaching position while Sasuke is off on his own personal quests. This shows Naruto's influence on the future of the ninja world. Another plotline could be that Naruto is the first to discover new ninja techniques or powers and uses them to better the village, leaving Sasuke to play catch - up.
After being promoted to chunin, Naruto's training would change significantly. He'd probably start training with more experienced chunin and jonin. They would teach him advanced combat techniques and how to better analyze his opponents. Also, he might have to study more about the politics and history of the ninja world, as chunin are often involved in diplomatic matters. His physical training would also intensify, but now it would be more about endurance and precision rather than just brute strength.
One interesting plot point could be Naruto having to overcome a personal fear. For example, he might be afraid of using a certain jutsu because it once backfired. But in order to prove himself worthy of Chunin, he has to master it. Another could be Naruto forming an unlikely alliance with a rival during the exams to defeat a common foe.
One popular Naruto promoted fanfiction is 'The Legacy of Naruto'. It delves into an alternate future where Naruto's teachings have spread far and wide, influencing a new generation of ninjas. Another great one could be 'Naruto's Ascendance', which focuses on Naruto achieving even greater power and using it to bring about a more unified ninja world. And 'Naruto: The Mentor' is also quite good, showing Naruto in a role of guiding the younger ninjas in Konoha.
One challenge could be leadership. As a Jounin, he'd have to lead teams. Naruto has always been more of a lone wolf in some ways, so coordinating and guiding others might be tough. Also, there would be more complex missions. He's used to straightforward 'beat the bad guy' type of missions, but now he has to deal with politics and long - term strategic goals.