A third plot could be that their presence in Ravenclaw changes the overall perception of the house. Usually seen as more cerebral and less action - oriented, Harry and Hermione bring a sense of adventure. They might convince their Ravenclaw housemates to join them in more dangerous quests, like exploring the Forbidden Forest for a rare ingredient for a potion that could help in the fight against the Dark Arts.
One idea could be that Hermione's thirst for knowledge takes a different turn in Ravenclaw. Instead of focusing mainly on academic success as she did in Gryffindor, she delves deeper into the more esoteric and theoretical aspects of magic. For example, she might start exploring ancient runes and their hidden meanings, which could lead her on adventures to discover lost spells.
One plot idea could be that Harry discovers a hidden diary of Helena Ravenclaw that reveals ancient spells and secrets of Hogwarts. This could lead him on a quest to uncover the true history of the school and his own connection to it. Another could be that Helena's spirit guides Harry through a difficult trial in the Room of Requirement, using her wisdom to help him make the right choices.
One idea could be that Harry discovers a long - lost diary of Rowena Ravenclaw. In it, he finds hidden spells and knowledge that help him in his fight against Voldemort. Another plot could be a time - travel scenario where Harry meets Rowena in her own time and they exchange ideas about magic, which then gives Harry new insights into the nature of magic at Hogwarts. A third plot might involve Rowena's ghost appearing to Harry and guiding him through a series of challenges within the Ravenclaw common room to unlock a powerful magical artifact that was once hers.
One interesting plot idea could be that Harry discovers a long - lost spell created by Rowena Ravenclaw. This spell might hold the key to defeating a new dark force at Hogwarts. Another could be that through some magical time - travel mishap, Harry meets Rowena Ravenclaw and has to help her protect an ancient magical artifact that is crucial to the future of Hogwarts. Maybe Harry also gets some insights into the early days of the Hogwarts houses and how Ravenclaw's values were first established.
A third idea could be a time - travel fanfiction. A character goes back in time to the era when the diadem was first made. They interact with Rowena Ravenclaw herself and learn about the true nature of the diadem. Then they bring this knowledge back to their own time to help in the fight against the dark forces that are once again interested in the diadem's power.
Well, a plot could involve Helena Ravenclaw's spirit being trapped in a cursed object, and Harry, with his unique connection to the magical world's mysteries, is the only one who can sense her distress. He then embarks on a quest to free her. Maybe there's a prophecy that ties Harry to Helena Ravenclaw, and they must work together (in a way, across time) to prevent a great evil from befalling Hogwarts. Also, it could be that Helena Ravenclaw's memories start to seep into Harry's mind, causing him to see the past of Hogwarts in a new light and leading him to uncover long - lost Ravenclaw knowledge that helps in the fight against Voldemort.
One idea could be that Hermione, as a Ravenclaw, uses her intelligence to solve a mystery within the school that no one else has been able to crack. For example, she discovers a hidden room with ancient magical knowledge that could change the way magic is taught at Hogwarts.
One plot idea could be that Harry, Hermione and Susan team up to solve a new mystery at Hogwarts that the teachers are overlooking. For example, a series of strange disappearances of magical creatures from the Forbidden Forest. They use their combined skills in magic, Hermione's research abilities, Harry's courage and Susan's unique knowledge of certain spells to track down what's happening.
One idea could be that in an alternate universe, Snape manages to save Lily and they both play a big role in Harry's upbringing along with Hermione. Maybe Snape uses his potions expertise and Lily's charm work to create a special protection spell for Harry that Hermione later helps to understand and strengthen. Another plot could be that Lily didn't die but was in hiding, and when Harry enters Hogwarts, Snape has to reconcile his feelings for Lily with his role as a teacher to Harry, while Hermione gets caught in the middle trying to figure out the truth behind their complex relationships.
Maybe in this 4th - year fanfiction, Harry and Hermione get involved in a Triwizard Tournament - like event but for younger students. They face challenges that test not only their magical skills but also their friendship. For example, one challenge could be to rescue a 'hostage' (a magical creature) from a dangerous enchanted forest without using their wands.