Perhaps a plot where the headmaster has to deal with a dark threat that is specifically targeting the school in a very different way than Voldemort did. This could involve some ancient magic being misused, and the headmaster has to use his or her wisdom and power to counter it while also protecting the students.
In some fanfictions, the headmaster might be a character from a different era or place who brings in a whole new culture of magic. This could lead to clashes and fusions of different magical practices within Hogwarts. For instance, if the headmaster was from a far - eastern magical community, we might see the introduction of different types of potions or spells based on that culture, and how the Hogwarts students and staff adapt to it.
Well, in some of these fanfictions, Harry might introduce new magical courses at Hogwarts. For example, he could start a course on ancient magical beasts that are not well - known. This would add a whole new dimension to the students' learning experience.
One interesting plot could be Harry dealing with the politics within Hogwarts as headmaster. He might have to face challenges from traditionalist teachers who oppose his more progressive ideas. For example, he could try to introduce new magical subjects that focus on Muggle - wizard relations, which would stir up a lot of debate among the staff and students.
Well, in some 'Harry is headmaster fanfic', there could be plots where Harry reforms the Hogwarts curriculum. He might introduce new magical subjects that were previously overlooked, like advanced Muggle Studies to improve the understanding between the wizarding and Muggle worlds.
One idea could be a fanfiction where the headmaster has to deal with a new, mysterious dark magic that is affecting the students' dreams. Another could be about a headmaster from a different wizarding school coming to Hogwarts for an exchange program and the chaos that ensues. Or perhaps a story where the headmaster discovers a long - lost spell in the Hogwarts library and has to decide what to do with it.
In my opinion, Dumbledore would still be a great headmaster in fanfiction. His wisdom and experience are invaluable. He always had a deep understanding of the students and was able to guide them through difficult times. He also had a great sense of humor and was very approachable despite his great power.
A popular choice could be a character like Sirius Black. If he had survived, he could have become headmaster with his rebellious yet caring nature. He would bring a different kind of leadership to Hogwarts, one that is more in tune with the students' desires for change and adventure.
A great plot could be that Harry decides to open Hogwarts to students from all over the world in a more inclusive way. However, this causes some cultural clashes among the students and staff. He has to find a way to make everyone feel welcome and at the same time maintain the school's traditions. Also, there could be a plot where a mysterious prophecy about Hogwarts is revealed, and Harry as headmaster has to figure out how to prevent its doom.
Another challenge would be handling the different houses. Each house has its own identity and sometimes rivalries can get out of hand. A new headmaster would need to find ways to promote unity among the houses, like through new inter - house competitions or joint projects.
In some Harry Potter 8 fanfictions, there are plots where the characters continue to face new dark magic threats. For example, a new dark wizard might emerge, and Harry, Hermione and Ron have to use their combined skills and knowledge to defeat this new foe. Another plot could be about the exploration of the wizarding world's past in more depth, revealing secrets that were previously unknown.
One interesting plot could be about the Potter family's hidden secrets being unearthed. Maybe there are ancient spells or prophecies related to them that no one knew before. Another could be a story where the Potter family has to face a new and powerful dark force that is specifically targeting them due to their legacy. And a third plot might involve time - traveling within the Potter family's history to correct past mistakes or learn from them.