Well, you could write about Spider - Man getting a new power in the fanfiction. Say, he somehow gains the ability to teleport short distances, which he has to learn to control while on a mission with the Avengers. Or, create a story where Spider - Man has to go undercover in a normal high school as part of an Avengers - related mission. He has to balance his superhero life with pretending to be a regular student again.
In an 'Avenging Spider - Man fanfiction', you might consider a story where Spider - Man is the only one who can save the other Avengers. For instance, the Avengers are trapped in a dimension where their powers don't work, but Spider - Man's spider - sense still functions. He then has to use his wits, agility, and that one working power to find a way to rescue his teammates. This could involve him facing off against strange new enemies in that dimension and making some tough choices along the way.
Some great avenging spider fanfiction stories involve crossovers. For instance, a story might bring in characters from other Marvel universes. Maybe Spider - Man meets a character from the X - Men while on an Avengers - related adventure. In some fanfictions, Spider - Man has to adapt to new technology provided by Tony Stark during an Avengers operation. This could lead to really cool action scenes and new ways for him to use his powers. Also, there could be a fanfiction where Spider - Man has to mentor a new young hero while being part of the Avengers.
One idea could be exploring the backstories of the different Spider - People in more detail. For example, how did Peni Parker really come to terms with her role as Spider - Woman in her own dimension. Another could be a crossover within the Spider - Verse, like what if Miles Morales and Gwen Stacy teamed up to face a new villain that was causing chaos across multiple dimensions.
There could be a lot of drama in the fanfiction related to the spider armor. For example, the public might react differently to this new armored version of Spider - Man. Some might see it as a sign of him becoming too militarized, while others might see it as a necessary upgrade. The armor could also be a target for villains who want to steal its technology for their own evil purposes.
One idea could be exploring the backstories of the different Spider - People more in - depth. For example, Peni Parker's relationship with her father and how it influenced her becoming Spider - Woman. Another could be a story where all the Spider - People have to team up against a new villain that is specifically targeting their multiverse connection. Maybe a villain who can disrupt the portals between their worlds.
One idea could be exploring the different Spider - People's home universes in more detail. For example, showing what Miles Morales' daily life in his universe was like before becoming Spider - Man. Another could be a team - up between Miles and an older, more experienced Spider - Person from a different universe to face a new and powerful villain.
Maybe a fanfiction where all the Spider - Men and Women from different spider - verses team up to fight a common enemy that threatens all of their universes. It could be a powerful cosmic entity that is consuming the multiverse, and they have to combine their unique skills and knowledge to stop it. This would allow for a lot of cool interactions between the different characters.
Perhaps there's a fanfiction where Spider Man and Spider Gwen accidentally swap powers. They have to learn how to use each other's abilities to fight crime. This would lead to some really funny and also challenging situations as they get used to different ways of web - slinging and sensing danger.
Another idea could be a story where Spider - Man has to help Ben 10 when the villains from his world start causing trouble in New York. They would have to combine their different skills and knowledge to protect the city and stop the bad guys.
One idea could be exploring a different origin story for Spider - Man in the fanfiction. Maybe he gets his powers from a scientific experiment gone wrong in a completely new way. For example, instead of being bitten by a radioactive spider, he could be exposed to a mutagenic serum that gives him spider - like abilities along with some unique side - effects that he has to deal with.
One idea could be that the mutant Spider - Man has the ability to communicate with other mutated animals in the city. He teams up with a mutant rat that has enhanced intelligence to uncover a criminal organization's underground lair.