In this fanfiction, it's possible that with his health fixed, Harry would have a newfound confidence. He could form stronger relationships with his friends and allies. For example, he might be more involved in Quidditch, leading his team to more victories, and also be more present in the fight against the Dark Arts, without any physical or mental hindrances.
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.
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.
In this fanfic, perhaps Harry discovers a hidden health issue. For example, he might find out he has a rare magical malady that only a few wizards have ever had. This could lead to a whole new adventure as he searches for a cure.
Well, it's possible that Harry gets a gadget that can translate any magical language instantly. This would be really useful when he's dealing with ancient spells or communicating with magical creatures from different regions. It could also lead to some comical situations, like when the gadget misinterprets a spell and creates a chaos of unintended magic.
In this fanfiction, Harry might use the staff for various magical purposes. Maybe it could enhance his existing powers. For example, it could help him perform more complex spells with greater ease. He could also use it to defend himself in a more unique way compared to just using his wand.
Well, perhaps Harry's new haircut makes him look completely different and his friends don't recognize him at first. It could be a humorous situation where they keep asking who he is until he reveals himself.
In this fanfiction, Harry might use the phoenix for various magical tasks. The phoenix could help him in his battles against Voldemort. For example, it could carry messages quickly or even heal his wounds with its tears.
In the 'Harry Potter gets knighted' fanfiction, perhaps Harry is honored for his heroic deeds against Voldemort. He might be knighted in a grand ceremony at Hogwarts, with all his friends and professors present. The Ministry of Magic could finally recognize his great contributions to the wizarding world.
In fanfictions about Harry getting his creature inheritance, he may inherit from a magical creature like a dragon. This could endow him with incredible strength and the ability to breathe fire (in a more magical and less destructive way, perhaps). It could also make him more resistant to heat and fire - spells related to fire might not harm him as much. This new inheritance would likely change his relationships too. His friends might be in awe of his new powers, and his enemies would be more cautious around him.
In the 'Harry Potter gets a second wand fanfiction', it could change his relationships too. His friends might be both amazed and a bit worried. Hermione would probably be eager to study the implications of having two wands. Ron might be a bit jealous at first. And Harry himself would need to learn how to balance the power of two wands, which could be a real struggle, both physically and mentally, as different wands have different 'personalities' and he'd have to master them both.
There's a chance that he'll meet some sort of magical creature that has made the cupboard its home. This could be a friendly creature that helps him get out or a more mischievous one that makes his situation even more difficult. He'll have to use his wits and magic skills to deal with it.