Well, Mary Jane would be one of the most affected. She has a deep emotional connection with Spider - Man. Ned, his friend from school, would be lost without him. And then there's J. Jonah Jameson. Even though he's often against Spider - Man, he might feel a strange sense of loss. Also, any villains who had a sort of twisted relationship with Spider - Man might also be affected in some way, like Venom or Green Goblin.
Well, often in 'ultimate spider man death fanfiction', the theme of heroism in the face of death is prominent. His death might be a result of a great battle against a powerful villain. It also might explore the concept of mortality, as Spider - Man, who seems so invincible at times, is now gone. And his death could lead to a new hero rising in his place, which is another possible theme.
Maybe he fakes his death to protect his loved ones from a powerful enemy. He could be trying to draw out a villain who has been targeting his family and friends.
It could be the Green Goblin. He's always been a major foe of Spider - Man and might be the reason for Spider - Man to fake his death, like if he's planning a huge attack and Spider - Man needs to deceive him to stop it.
Yes, it could be. If the copyright holders were to be more lenient and even encourage fanfiction in a controlled way, it could revive. For instance, they could set up official channels or competitions for Spider - Man fanfiction, which would attract more writers.
Another aspect is the emotional impact on the readers. Fanfiction writers who choose to kill off Spider - Man are playing with the readers' attachment to the character. It can create a strong sense of shock and sadness, but also lead to interesting character development for the remaining characters in the story.
Even one of Spider - Man's fellow superhero friends might betray him. Maybe they get jealous of Spider - Man's popularity or feel that he is getting all the credit for their team's successes. This internal betrayal would add a lot of drama and conflict to the fanfiction story.
Doctor Octopus is also a likely candidate. His mechanical arms and high intelligence could give him an edge. He could manipulate a situation where Peter is caught off - guard and unable to defend himself, resulting in his death.
One possible fanfiction could be about Peter Parker using his Spider - Man abilities in a snow - covered city during a cold snap. Maybe he has to deal with villains who are taking advantage of the difficult weather conditions. For example, a villain could be using the snow and ice to create dangerous traps for the citizens, and Spider - Man has to swing through the icy streets to stop them.