Another aspect could be the destinies of the secondary characters. For instance, Neville Longbottom might become the 'chosen one' in the fanfic. His journey to fulfill this new role, considering his shy and clumsy nature at the start, would be full of twists and turns. He would have to overcome his self - doubt and grow into a powerful wizard in a different way than Harry did in the original series.
The fanfic might also play with the idea of the wizarding world's destiny as a whole. What if Voldemort had actually won in the end? How would the wizarding world be ruled? Would there be a resistance? This kind of exploration of the overall destiny of the magical realm can lead to some really engaging and thought - provoking storylines.
One interesting idea could be exploring an alternate destiny for Harry. Maybe he becomes a Slytherin instead of a Gryffindor. This would completely change his relationships and how the story unfolds.
One idea could be to have the characters from Harry Potter interact with the Guardians from Destiny in a battle against a common dark magic - influenced enemy. For example, Harry Potter could team up with Cayde - 6 to fight off a horde of Death Eaters and Fallen that have somehow merged their powers.
Perhaps the Voldemort threat in the Harry Potter world is somehow connected to a Darkness - like entity in Destiny. Harry and his friends must learn new combat techniques from the Guardians or other Destiny characters to combat this new, more powerful form of the Dark Lord. They could also exchange magical and technological knowledge, which would be really cool to see.
One interesting plot could be that Harry is sorted into Slytherin instead of Gryffindor. This would completely change his relationships and how others perceive him. His friendships might form with different characters, like Draco Malfoy becoming a more positive influence on him rather than an antagonist.
A great 'Harry Potter fanfic' idea might be a story that delves deeper into the relationship between Snape and Lily. Maybe a fanfic where Snape has a chance to change the past and save Lily in a different way. Another idea is to write a fanfic about the ghosts in Hogwarts and their backstories, like how they died and why they chose to stay at the school. Additionally, a story where the Weasley twins open a magical joke shop in a different country and the challenges they face there would be really interesting.
One interesting idea could be a fanfic that focuses on the Marauders' time at Hogwarts. It could explore their pranks, friendships, and how they came to be the legends that we hear about in the original books. For example, showing how they created the Marauder's Map in more detail.
One interesting idea could be exploring the lives of the minor characters more in - depth. For example, what was Neville Longbottom's life like during the summers at home? Another idea is to create an alternate ending to the series. Maybe Voldemort could have been redeemed instead of defeated. Also, a fanfic could focus on the magical creatures and their own society within the wizarding world.
One interesting idea could be a fanfic where the Marauders attend Hogwarts during modern times. They'd have to deal with things like smartphones and social media while still maintaining their mischievous ways. Another could be a story that focuses on the lives of the house - elves after the events of the books, perhaps exploring their newfound freedom. And a third idea could be a fanfic about a new dark wizard emerging in the wizarding world years after Voldemort's defeat, and how the new generation of Hogwarts students respond.
One idea could be exploring how the eldritch elements interact with the magic in Hogwarts. For example, an eldritch force might seep into the Forbidden Forest and start to corrupt the magical creatures there, leading to strange and dangerous new behaviors among them. Another could be about a student who discovers an eldritch spellbook in the Room of Requirement and has to deal with the unforeseen consequences of using its spells.
One idea could be a letter from a Hogwarts student to their parents explaining their first experiences in the Forbidden Forest. It could detail the strange creatures they saw and the sense of danger and excitement.
You could also create a fanfic centered around the Thestrals. For example, a story where a group of students discover a hidden colony of Thestrals and have to protect them from dark wizards who want to use their powers for evil. Since only those who have witnessed death can see Thestrals, it could add an interesting mystery element to the story.