Perhaps the dog was actually a cursed form of someone Harry knows or will know in the future. After the attack, as Harry recovers, he starts noticing strange behavior from certain people. This could lead to a sub - plot where Harry is trying to figure out who the dog really was. Meanwhile, his relationship with those around him might change. Some people might be more sympathetic towards him because of the attack, while others might think he's overreacting. All these things can add depth to the fanfiction story.
One possible plot development could be that Harry develops a fear of dogs. This fear might then become a character trait that affects his actions in other situations. For example, he might be hesitant to enter certain areas where he suspects dogs could be present. Another development could be that the attack was not accidental. Maybe there's a dark wizard using the dog as a tool to harm Harry, and this discovery could lead to a whole mystery-solving adventure for Harry and his friends.
The attack could lead to Harry having to stay in the hospital wing for a while. During this time, he might have strange dreams or visions related to the dog or the event. This could be a sign of some deeper magic at work. It could also be a way for the author to introduce new magical creatures or spells that are used to heal him. And his friends, like Hermione and Ron, could be by his side, trying to cheer him up and also figure out why the dog attacked him.
Harry might react with fear. He could be traumatized by the experience and be constantly on edge, jumping at the slightest sound. This fear could make him more cautious in general.
Well, perhaps they could become friends quickly. Bill might introduce Harry to some interesting magical things he hasn't seen before, like some unique creatures. And they could start having little adventures together around the wizarding world.
Well, it could be that there's a misunderstanding. Maybe some Gryffindor students think Harry has done something wrong, like he's been framed for a crime in Hogwarts. So they turn against him in anger and attack him. But later they find out the truth and feel really guilty.
One interesting plot development could be Severus having to adjust his teaching style at Hogwarts. Since he has adopted Harry, he can't be as harsh as he used to be towards him in class. This would create a new dynamic between them at school. Also, Severus might have to deal with the other teachers' reactions to this new situation.
One possible plot development could be that Harry kills Umbridge in self - defense. Maybe she attacks him first with the intent to harm or kill, and Harry has no choice but to use lethal magic in return. This would then lead to a huge uproar in the wizarding world, with some believing Harry was right and others seeing him as a murderer.
One possible plot development could be how the wizarding world reacts to the loss of the so - called 'Chosen One' even as a baby. There might be widespread grief and fear among those who opposed Voldemort, as they had placed so many hopes on Harry. Another aspect could be how Voldemort's reign of terror continues without the threat of Harry Potter. He might become even more powerful and tyrannical, with no one to oppose him in the way Harry was prophesied to.
One possible plot development could be that with Merlin's help, Harry discovers a new form of magic that was previously unknown. This new magic could then be used to defeat a powerful enemy.
The fact that Harry is sorted into Ravenclaw could also cause a rift with some of his Gryffindor friends at first. However, as time goes on, they could come to see the benefits of his new House. Harry might introduce some Ravenclaw values like open - mindedness to Gryffindor. And his Ravenclaw housemates could also learn about loyalty and bravery from Harry. This could lead to a more united Hogwarts against Voldemort, with all the Houses working together in new ways.
Well, one possible plot development could be that Harry learns some really unique combat skills from Scathach. Maybe he becomes a much more formidable wizard in dueling. Another could be that he gains a different perspective on magic through her teachings, which helps him in his battles against Voldemort.
One possible plot development could be that his friends rally around him. They might search for rare potions or spells to heal him. For example, Hermione could be scouring the library for ancient healing magic while Ron stays by Harry's side, offering moral support.