Another plotline could be that Naruto's long black hair is a key to unlocking an ancient power. There are prophecies about a ninja with long black hair who will save the village or the whole ninja world. So Naruto has to figure out how to use his hair to access this power. Along the way, he might face many challenges and enemies who want to stop him from fulfilling the prophecy.
One plotline could be that Naruto's long hair is a sign of a connection to an ancient power. He has to learn to control this power which is linked to his long hair. Along the way, he meets other characters who have knowledge about this power and his long hair becomes a central part of his journey to master this new ability.
One possible plotline could be that Naruto's silver hair is a result of a powerful curse placed on him. This curse could be related to an ancient evil that is trying to use Naruto as a vessel. So, the story could revolve around Naruto trying to break this curse while still being the hero he is. Another plotline might be that his silver hair is a sign of a new chakra form he is developing. He then has to learn how to control this new form and use it to protect the village from a new threat.
A possible plotline could be that Harry's long hair is a result of a curse. He then has to go on a quest to find the antidote, all while dealing with the challenges of having such long hair, like it getting in the way during his classes or Quidditch matches.
In some fanfictions, Harry's long hair might give him special powers. For instance, it could be a sign that he has a connection to an ancient magic. The plot could revolve around him exploring this new connection and using it to fight against Voldemort in a different way than in the original books. The long hair could also attract the attention of new characters, like a mysterious wizard who recognizes the significance of his long hair and offers to train him further.
Well, one plotline could be that his red hair is a result of a curse. He then has to find a way to break the curse, all while dealing with his regular Hogwarts life, like exams and Quidditch. Another could be that his red hair is a sign of a new magical power awakening within him.
It could be part of a beauty - and - the - beast - like story where Harry's silky hair is what initially draws someone to him, but they have to look past his other 'imperfections' or his difficult situation. For instance, if he's still living with the Dursleys and his silky hair is like a glimmer of hope or beauty in his otherwise tough life.
A plotline might involve Naruto's struggle to maintain his status as a ninja while dealing with the cancer. He could face discrimination from some in the village who think he's no longer fit for duty. Or there could be a plot where the Akatsuki somehow find out about his condition and try to use it to their advantage, like blackmailing him or using it as a distraction in a battle.
A possible plotline could be that the Ketsuryugan gives Naruto the ability to see the true nature of people's chakra, which causes him to question some of his relationships. He might discover that some people he thought were friends have ulterior motives. Also, there could be a story where Naruto uses the Ketsuryugan to develop a new form of his Rasengan, combining the power of the Ketsuryugan with his existing skills. This new ability could then be the key to defeating a powerful and previously undefeatable enemy in the fanfiction.
One possible plotline could be Naruto discovers he has a hidden Fullbring ability. He then has to learn to control it while still dealing with the threats in his own world. Maybe he uses it to fight stronger enemies like Madara in a new and unexpected way.
One possible plotline could be a power - exchange. Naruto learns about the power of Vibranium from Black Panther and tries to incorporate it into his ninja tools. Meanwhile, Black Panther gets interested in chakra and starts training to use it.