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 plot could be that Harry as headmaster focuses on improving the relations between different houses. He might organize more inter - house activities like a grand magical tournament where students from all houses have to team up. This would break the traditional rivalries and create a more united Hogwarts.
In certain fanfictions, Harry as headmaster might face a threat from an old dark magic that has been dormant for ages. He then has to use his unique experiences and knowledge to not only protect the school but also find a way to permanently vanquish this new threat. He might seek help from old friends and even some former enemies turned allies.
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.
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 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, perhaps a plotline where Harry has to deal with a new dark threat that is targeting Hogwarts specifically. As headmaster, he would use his knowledge of the Dark Arts and his friends' expertise to protect the school. He could also start new traditions at Hogwarts to boost the morale of students and staff alike.
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.
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.
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.
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.
One interesting plot could be Harry, using his magic skills, accidentally transports himself to Elsa's world. There, he helps Elsa better understand and control her powers in a different way than she's used to. They might also team up to fight a common threat that endangers both the wizarding world and Arendelle.
Perhaps a plot where Sanguini helps Harry understand some ancient vampire - related magic that has a connection to Voldemort's rise. It could involve Sanguini teaching Harry about certain spells or artifacts that are related to the vampire world and how they are being misused by the dark forces.