There might be a fanfiction where Vernon has to enter the wizarding world himself for some reason. It could be really funny to see how he copes with all the magic and strange things around him. He'd probably be very out of place and his typical gruff attitude would make for some interesting interactions with the wizards.
Some fanfictions might explore a backstory for Uncle Vernon. Perhaps he had an encounter with a wizard when he was younger that made him so bitter towards magic. In these stories, Harry could discover this secret and it could change their relationship. Also, there could be a plot where Uncle Vernon is magically turned into a wizard for a short time. This would be a comical yet thought - provoking plotline as he would have to navigate a world he once despised.
One interesting fanfiction could be about Vernon Dursley having to face a magical threat in the Muggle world on his own. He might have to rely on some of the little knowledge he has about the wizarding world through Harry. Another could be a story where Vernon and Harry are forced to work together during a crisis that affects both the Muggle and wizarding communities, changing their relationship completely. There could also be a fanfiction exploring Vernon's past and how it might have influenced his treatment of Harry, and then how things could have been different if certain events in his past were changed.
One interesting fanfiction could be about Vernon Dursley's perspective during the time when Harry first received his Hogwarts letter. It might explore his extreme reactions and the inner turmoil he felt at the thought of magic being real. Another could focus on a situation where Vernon has to interact with the wizarding world in an unexpected way, like when he accidentally stumbles into Diagon Alley.
The 'harry potter gagged by vernon fanfiction' could be about a particular situation where Vernon restricts Harry Potter's ability to speak. This might be part of a larger plot in the fanfiction. For example, it could be set in a scenario where Vernon has discovered some of Harry's wizarding secrets and in an attempt to keep them from getting out, he gags Harry. Or perhaps it's a more psychological exploration where Vernon's abuse of Harry takes on a new form of silencing him, and the story could then delve into how Harry overcomes this obstacle, or how it affects his relationships with other characters like Hermione and Ron.
Good Vernon Harry Potter fanfiction usually has a fresh perspective. It might explore Vernon's past to explain his present behavior. For instance, perhaps he had a bad experience with a wizard when he was younger that made him so anti - magic. It should also have engaging plotlines. Instead of just repeating the same old interactions between Vernon and Harry, it could introduce new conflicts and resolutions. And the writing style matters. If the author can write in a way that makes Vernon seem real and his story interesting, then it's a good fanfiction.
Well, perhaps Vernon might beat Harry out of his extreme dislike for magic. He could be enraged by some accidental magic Harry does at home and lose his temper completely.
One great Vernon - related Harry Potter fanfiction is 'The Unseen Side of Vernon Dursley'. It shows a different perspective of Vernon, exploring his insecurities and how his interactions with Harry might have been influenced by his own fears. Another one could be 'Vernon's Redemption'. It's an interesting take on Vernon gradually changing his views on magic and Harry as the story progresses.
In some fanfiction, Uncle Vernon develops by becoming more accepting. For instance, he may start to see Harry not just as a freak but as a person with unique abilities that can be useful. He might begin to tolerate the wizarding world a bit more, especially if he realizes that Harry can use his magic to protect the family from certain threats.
I'm not really into slash fanfiction myself, but you could try searching on some popular fanfiction websites like FanFiction.net or Archive of Our Own. There might be some unique takes on the relationship between Harry Potter and Vernon Dursley in those platforms.
The contrast between their characters. Harry, even as a female, is a magical being full of wonder and potential, while Vernon is a very mundane and often narrow - minded Muggle. This creates a lot of interesting conflict and opportunities for unique storylines.