The plot might involve Harry being part of a gang that is formed to protect the Muggle - born students. They operate in the shadows, using their combined skills to counter any threats from the pure - blood supremacist groups. They could be led by an older student who has seen the discrimination first - hand and is determined to stop it.
Harry himself would be one of the main members, of course. Hermione could also be part of it, using her vast knowledge of magic to the gang's advantage. Neville might join too, having proven his courage time and time again. And perhaps some of the Weasley twins' friends from their pranking escapades.
One possible plot could be that Hogwarts students discover a Stargate on the school grounds. Maybe it was hidden by a powerful wizard in the past who had visited other planets through it. The students, led by Harry Potter, could then start to explore different planets through the Stargate. They might encounter alien races that have magical abilities similar to theirs, leading to a cultural exchange of magic and technology.
One possible plot could be that Harry, tired of the Ministry's inaction against dark wizards, forms his own gang. They could be a group that operates in the shadows, protecting the weak. For example, they might start by rescuing Muggle - borns who are being persecuted. Harry, using his skills and knowledge from Hogwarts, trains his gang members in defensive magic. They could also have a hideout, perhaps an abandoned wizarding house. Their main goal would be to bring justice to the wizarding world in their own way.
Harry's gang could include some of the characters we don't see much of in the original books. For example, the house - elves. Dobby was already very loyal to Harry. Maybe he could convince other house - elves to help out in a more active way. There could also be some of the older students who dropped out of Hogwarts for various reasons but still have a lot of magical knowledge. And of course, Hagrid could be an honorary member, providing his vast knowledge of magical creatures and his big - hearted support for Harry and the gang.
Well, maybe Harry joins the gang to protect his friends. He could be using his skills, like the ones he learned at Hogwarts, in a different way to gain the gang's respect.
The fanfic could center around Harry's life outside of the main events of the books. For example, it could explore his summer holidays in more detail. He could be spending time in the Muggle world and using his magic in creative ways to solve normal, everyday problems. He might use magic to help his neighbor fix a broken fence without the neighbor realizing it was magic. This would add a new dimension to his character and show how he can adapt his magical abilities to different situations.
One possible plot could be that Harry Potter is hired by Sherlock Holmes to help with a case that involves dark magic. Harry uses his knowledge of the wizarding world to uncover clues that Sherlock couldn't find with just his deductive skills.
Imagine Harry Potter as a bartender. He could be using his skills not just in mixing drinks but also in reading people. Since he has faced so many challenges in his life, he can easily spot if a customer is hiding something or if they are in trouble. His bar could become a place where secrets are shared, and he has to use his wits and magic to keep things in order. He might also have to deal with rival bartenders from other wizarding establishments who are jealous of his popularity and unique drinks.
The plot could involve Harry Potter discovering he has some sort of connection to a dragoness. Maybe he can communicate with her telepathically. They could team up to fight against dark forces in the wizarding world. For example, Voldemort might be after the dragoness for her powerful magic, and Harry has to protect her while also using her strength to defeat Voldemort.
One possible plot could be a deaf Muggle - born student getting their Hogwarts letter. They face difficulties in the beginning as they can't hear the instructions well. But they soon discover a magical device that helps them 'hear' in a magical way, like through vibrations that translate into words in their mind. Then they go on to prove themselves in classes like Charms and Potions, making friends along the way.