Another plot might involve Harry using his Gryffindor - like courage to change the Slytherin house from within. He could introduce new ideas of friendship and loyalty that are not typically associated with Slytherin. This would cause a stir among the Slytherin students and faculty, and Harry would have to face both support and opposition as he tries to reshape the Slytherin image.
One interesting plot could be Harry having to deal with the Slytherin's traditional pure - blood supremacist views while trying to stay true to his own values. He might face challenges from some of his Slytherin housemates who initially look down on him for his 'half - blood' status.
There could also be a plot where Hermione discovers a long - lost Slytherin secret. It might be a powerful spell or a hidden chamber that only a Slytherin with her unique combination of knowledge and determination can unlock. This discovery then changes the way Slytherin is perceived in the wizarding community.
Another plot could involve Harry discovering some long - lost Slytherin secrets. Maybe there are hidden chambers or spells that only Slytherin students are supposed to know about. Harry, being the curious and brave character he is, delves into these secrets. This could put him in a dangerous position as some Slytherins might not want him to expose or use these secrets, but it also gives him a chance to prove himself to his new housemates.
Some fanfictions might have a plot where Harry goes to Azkaban to rescue someone. It could be a friend or a relative who has been wrongly accused. Along the way, he has to navigate the dangerous corridors of Azkaban filled with various traps and curses. He might also meet some old enemies who are also in Azkaban and they try to stop him from achieving his goal. In addition, the magic that keeps Azkaban intact could be a key part of the story, like Harry has to figure out how to manipulate it to his advantage.
Another plot might involve Harry facing a new kind of dark magic threat at the university. This could be a dark magic that is specific to the academic environment, like a curse on a certain magical textbook that starts spreading chaos among the students. He has to use his skills and knowledge gained at Hogwarts and develop new ones to deal with it.
Well, one interesting plot could be Harry making new and unique friends at the magical university. Maybe he meets a group of students from different magical backgrounds and they form a study group that gets into all sorts of adventures while trying to master new spells.
In some 'Harry Potter Goes Traveling' fanfictions, Harry might travel through time as well as space. He could go back to the time of the founders of Hogwarts to learn the original magic. Or he might visit different historical periods in the wizarding world, like the time of the Great Wizarding War in other countries. This would give him a broader perspective on the history of magic and how different wizarding cultures have dealt with conflict. Also, he could meet his ancestors or relatives from different parts of the world who were wizards and learn about his family's magical heritage.
In some fanfictions, Harry goes back in time and decides to train himself better. He could seek out different magical knowledge or combat skills that he didn't have the first time around, which then changes his future interactions and battles. For example, he might learn ancient spells that give him an edge against Voldemort.
A possible plot is that Harry's inner Slytherin makes him question the whole Hogwarts house system. He might start a movement within the school to break down the barriers between the houses. This causes a stir among the students and faculty alike. He uses his Slytherin - like charm and Gryffindor courage to persuade others to see that they are all more alike than they seem, regardless of their house affiliations.
Another plot could be Hermione trying to reform the Slytherin House from within. She might introduce new study groups or a more inclusive attitude towards non - pure - blood students. This would likely face a lot of resistance from some of the more traditional Slytherin families, but Hermione, with her determination, could start to make small but significant changes.
Draco Malfoy is a very common character. Since they are in the same house in this fanfiction concept, their interactions would be different from the original story. There would likely be more opportunities for them to either become friends or rivals in a new way.