Maybe Spider - Man discovers a new threat that the Avengers have overlooked. He then tries to convince them of the danger, facing skepticism at first but eventually winning them over with his tenacity and evidence. For example, he could find a hidden group of villains planning to use a new type of technology to take over the world.
Maybe in the fanfiction, Spider - Man discovers a secret connection between his powers and an ancient Asgardian artifact. The Avengers, especially Thor, would be intrigued. They then embark on a journey to figure out how this connection could either save or endanger the world. Spider - Man would have to balance his normal life and this new discovery with the Avengers.
A great plot for Amazing Spider - Man fanfiction could be a time - travel story. Spider - Man could be sent back in time to the era when his powers first emerged. He could then use his knowledge of the future to prevent some of the tragedies that occurred in his past, like the death of Uncle Ben. Or, he could be sent to a future where New York has become a dystopia, and he has to find a way to fix it and return to his own time.
One plot idea could be the Avengers recruiting Spider - Man to help with a new threat in the PS4 game's version of New York. Maybe a powerful villain from the Avengers' rogues gallery has teamed up with one of Spider - Man's foes.
One interesting crossover could be Spider - Man using his agility and web - slinging skills to help the Avengers in a city - based battle. His ability to move quickly through the skyscrapers can give the Avengers an edge in a fight against villains who are causing chaos in a metropolis.
A possible plot is that Spider Girl gets transported to an alternate dimension where the Avengers are different. She has to find a way back home while also helping this new version of the Avengers deal with a threat that she's familiar with from her own world. For example, maybe a version of Doctor Octopus is causing chaos there. She uses her wits and powers to not only survive but also to try and set things right in this strange new dimension.
One idea could be exploring a new villain that is created from a scientific experiment gone wrong in Oscorp. This villain could have powers related to electricity and pose a new threat to Spider - Man.
One idea could be Spider - Man joining the Avengers on a mission to a far - off planet. He uses his agility and quick thinking to help the team out of tricky situations. Another could be a story where Spider - Man has to prove himself to the Avengers in a training exercise set up by Iron Man.
One interesting storyline could be Spider - Man teaming up with the Avengers to fight a new super - villain that's a combination of different powers they've faced before. For example, a villain with the strength of the Hulk and the mind - control abilities of Loki.
One plot idea could be that Gwen discovers a new superpower that she has to learn to control, and Peter helps her through the process. This could add a new dynamic to their relationship as they both have different powers and ways of handling them.
A crossover with the Avengers is also great. Picture Spider - Man having to prove himself to the more established heroes like Iron Man and Captain America. He could bring his unique street - level hero skills to a big - scale Avengers mission.