The Green Goblin could be a great main villain in a crossover. Imagine if he teams up with Doctor Doom from the Fantastic Four universe. Their combined evil intelligence and power would be a huge threat to Spider - Man and whoever he teams up with in the crossover.
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.
One possible plot could be that Spider - Man gets accidentally transported to the Avengers' headquarters. He has to prove himself to the Avengers at first, since they don't really know him well. Then, they discover a common enemy that is planning to attack both New York City (Spider - Man's territory) and other major cities around the world that the Avengers protect. Together, they combine their powers and skills. Spider - Man's agility and spider - sense work well with Iron Man's technology, Captain America's leadership and combat skills, Thor's godly strength, etc. They have to overcome their differences in fighting styles and strategies to defeat the enemy.
One great fanfiction could be about Spider - Man joining the Avengers for a mission against a powerful new villain. In this story, Spider - Man's unique abilities like his agility and web - slinging would add a new dynamic to the Avengers' combat strategy. Maybe he helps Iron Man with some technical glitches during the fight while also using his street - smart skills to gather intel. Another interesting crossover could be a story where Spider - Man has to train some of the newer Avengers members, like Scarlet Witch. His experience as a solo hero in the streets of New York gives him a different perspective on heroism compared to the more global - scale Avengers.
It expands the universe by introducing new characters. Fanfiction writers can create their own original characters that interact with Spider - Man. These characters could be other superheroes, villains, or just normal people who get caught up in Spider - Man's world. For example, a new hero who teams up with Spider - Man to fight a common enemy.
One of the best moments could be when Spider - Man first meets the Avengers. The look of shock or admiration on his face (or theirs) would be really interesting to read. It's a moment of two different worlds colliding.
One great fanfiction idea could be Harry Osborn's internal struggle with his new - found powers in 'The Amazing Spider - Man 2'. He might be torn between using them for good, like Spider - Man, or for his own self - interests. For example, he could be constantly fighting the urge to use his powers to gain more control over Oscorp, while also being aware that Spider - Man's way of using powers is more noble.
Some fanfictions give Spider - Man the power to heal himself much faster. This means that even after a really tough fight, he can get back on his feet in no time. In addition, he might have the power to fly using his webs in a more efficient way, like creating a sort of web - glider that can carry him long distances. There could also be a power where he can project his thoughts into the minds of others, which would be useful for both communication and misdirection.
It's about Peter Parker's continued adventures as Spider - Man. He faces new villains like Electro. There are also his relationship struggles, especially with Gwen Stacy. It shows his attempts to balance his normal life and his superhero duties.