It could be a stray wizard who happened to pass by Harry's place and noticed his magical potential. This wizard might take pity on Harry and start teaching him a bit about magic.
Perhaps an old family friend of the Potters who is a wizard and has been secretly keeping an eye on Harry. Once he realizes that Harry is showing signs of his magic, he decides to start teaching him. This person could have known Harry's parents well and feels a sense of duty to pass on some magic knowledge to Harry.
One interesting plot could be that Harry discovers he has magic through an encounter with a magical creature in his neighborhood. For example, he might meet a house - elf who accidentally reveals some magic to him. Another plot could involve Harry finding a hidden magic book in his aunt and uncle's attic that teaches him basic spells.
Well, in the original Harry Potter series, black magic is clearly depicted as something evil. So from the perspective of the original lore, it's not ethical. Black magic often involves harming others and going against the basic moral principles in the wizarding world. However, in fanfiction, it can be a thought - experiment of sorts. Some might argue that it's just exploring a different side of a character, but it still treads on dangerous moral ground.
It could be a former member of the Weird Sisters. Given their fame in the wizarding world of music, one of them might decide to teach at Hogwarts. They would bring a lot of rock - like energy to the class.
It would be a disaster. The Hogwarts environment is all about nurturing young wizards and witches, while Orochimaru - like character would be more interested in using the students for his own dark purposes, like experimenting on them or using their magic for his gain.
There are fanfictions where Hogwarts teachers are given different personalities. Like a Snape who is more approachable and befriends the students in a different way. He could be involved in a plot where he teams up with other teachers to solve a mystery that threatens Hogwarts. Maybe it has to do with a dark force that is slowly corrupting the school's magic defenses.
Dumbledore is often a popular character. In fanfiction, he might be explored in more depth, like his early years as a wizard or his relationships with other powerful wizards that were not fully shown in the original books. His wisdom and power make him a great subject for new and exciting stories.
The History of Magic teacher at Hogwarts School of Witchcraft and Wizardry was Professor Cuthbert Binns, who was a ghost. He was old and stubborn, wheezing and drawling when he spoke, and the class format was always the same, always following the textbook, which made his class very boring. Harry Potter and the Prisoner of Azkaban wasn't enough. Everyone, please click to read the novel!
In the learning trunk, there might be a magical map similar to the Marauder's Map but with more detailed information about the Hogwarts library. It could show hidden sections and the location of books related to specific spells or magical theories. There could also be a set of magical crystals that when held, can transport him into virtual scenarios to practice spells and combat skills in a safe environment.
The learning trunk might offer him a more personalized learning experience. For example, if he's struggling with a certain spell, the trunk could provide a step - by - step guide or even a magical tutor in the form of a spell - casted projection. Also, it could give him the opportunity to study at his own pace without the distractions of a classroom. He can focus on the areas he's most interested in or needs to improve on, like advanced transfiguration or advanced defense against the dark arts.