Dumbledore could also be a key figure. He has so much knowledge and wisdom that he might know some ancient magic or spell that could cure Harry. He could guide Harry through the process of getting his health fixed and offer moral support as well.
Well, perhaps Harry would finally be able to fully focus on his studies at Hogwarts without being held back by any lingering health issues. He could become even more proficient in magic, and might be able to take on more challenging tasks and adventures.
Harry is, of course, the main character. Neville could be an unexpected helper. Maybe he has come across a rare herb during his Herbology studies that has the potential to heal eye problems. And Luna Lovegood might also be part of it, with her unique insights and knowledge of the wizarding world's more esoteric aspects, she could offer some unorthodox but effective solutions for Harry's eye problem.
Obviously, Harry Potter himself is the central character as the story is about him getting top owl results. Hermione would also be important as she is always the one to help Harry with his studies.
Ensure the conflict is well - defined. In the original Harry Potter books, there was always a clear threat, like Voldemort. In fanfiction, the conflict should be equally engaging. Maybe it's a new dark wizard or a different kind of magical danger. Also, the resolution of the conflict should be logical. It can't be something too far - fetched or too easy. If the characters face a seemingly impossible situation, they should overcome it through their skills, wits, and the help of their friends, just like in the original series.
Hermione Granger is a very common character. Since she is Harry's best friend, she would likely be there to help him understand and control his new superpowers. She might research in the library to find out how these powers came about and how to use them effectively. Ron Weasley is also common. He would probably be both in awe and a bit jealous of Harry's new powers at first but would still support him in the end.
Ron would also be there. He might start out a bit reluctant, but then get into it. He could be Harry's partner in physical challenges, like having races on broomsticks or wrestling magical creatures in a controlled environment for fitness.
Sometimes, new original characters are created in fanfiction to help Harry. These could be students from other wizarding schools who have unique skills. For example, a student from a school in a far - off land who has mastered a type of magic that is unknown in Hogwarts and uses it to help Harry in his fight against the dark forces.
Hermione would be very concerned and would immediately start looking for a solution in the library. She'd be flipping through every magical book she could find, trying to figure out what spell or potion could reverse the effect. Ron would be a bit shocked at first but then would try to protect Harry as best he could. He might be a bit clumsy about it, like trying to keep Harry out of trouble in the Gryffindor common room. Dumbledore would likely be calm and observant. He'd probably already have some ideas about what's going on and would be subtly guiding the situation to ensure Harry's safety and the well - being of the wizarding world.
Obviously, Harry Potter himself is the central character as he's the one getting the wish. Hermione and Ron are also commonly involved. They are Harry's best friends, so they would be there to support him or perhaps even influence his wish. Dumbledore also often shows up in these fanfictions. As the wise headmaster, he might guide Harry on how to use his wish wisely or warn him of the consequences.
Obviously, Harry Potter himself is the central figure. His friends like Ron and Hermione would also be involved. They would support Harry in his revenge plans, with Ron providing his loyalty and Hermione using her intelligence to strategize. Ginny Weasley might also be part of it, as she is Harry's love interest and a strong - willed witch in her own right.