Another plot could be that Spider - Girl gets injured and Mary Jane has to take on some of her responsibilities temporarily. Mary Jane could learn some basic web - slinging skills from Spider - Girl's gadgets and use her wits to fight off small - time criminals. This would show Mary Jane's growth from a damsel in distress to a capable helper.
One idea could be Mary Jane discovers Spider - Girl's secret identity by accident and they team up to take on a new villain in town. Maybe a villain who can manipulate emotions, and Mary Jane uses her acting skills to help Spider - Girl deceive the villain.
A great plot idea would be Mary Jane being kidnapped by one of Spider - Man's enemies who wants to use her as bait. Peter has to use all his skills and intelligence to rescue her without revealing his identity to the kidnapper. Also, Mary Jane could start training in self - defense secretly and ends up helping Spider - Man during a fight without him knowing it was her at first.
Perhaps there's a plot where an alien symbiote attaches itself to Mary Jane instead of Peter. She starts to develop strange powers and a more aggressive personality. Peter has to figure out how to save her from the symbiote's control. This would put a strain on their relationship as Mary Jane struggles with the new - found power and Peter tries to be the hero she needs.
One idea could be Mary Jane starting her own investigative journalism project related to Spider - Man's enemies. This would put her in danger and force Spider - Man to protect her while also trying to keep his identity a secret from her new inquiries.
One interesting scenario could be Spider Man using his web - slinging skills in a really creative way to rescue Mary Jane from a collapsing building. He might swing in at the last moment and carry her to safety while debris falls all around them.
One plot idea could be Peter and Mary Jane going on a double - date with another superhero couple. It would be interesting to see how they interact in a more normal social setting while still having their superhero identities in the background. Another idea is a story where Mary Jane gets some of Spider - Man's powers temporarily. This could lead to her having to learn how to use them quickly while Peter tries to help her. A third idea could be a time - travel story where they go back to the early days of Peter becoming Spider - Man and Mary Jane first getting interested in him, and they have to relive those moments with their current knowledge and relationship status.
In some Spider - Man fanfictions, Mary Jane being pregnant can add a whole new layer of drama. It could mean that Spider - Man has to balance his superhero duties with being a soon - to - be father. Maybe he'll worry about protecting his family more than ever, and there could be new villains who target his unborn child or Mary Jane to get to him.
In 'The Unseen Mary Jane', the plot twist where Mary Jane discovers she has latent superpowers is really cool. It completely changes the dynamic of her relationship with Spider - Man. Another one is in 'MJ's Secret Identity' where it's revealed that Mary Jane has been secretly working with an underground superhero organization all along.
Mary Jane could react with shock at first. After all, it's a huge secret to be revealed.
One interesting plot idea could be that Spider Girl and Spiderman team up to take on a new supervillain who has the power to control time. They have to figure out how to defeat the villain while also dealing with the chaos caused by the time - warping powers. Another idea is that Spider Girl discovers a secret about Spiderman's past that changes their relationship. Maybe she finds out about an old enemy he had that is now back and they have to face it together.
The Vulture could be a great villain. He could target Mary Jane to get to Spider - Girl, thinking that Mary Jane is a weak point. His aerial attacks would pose a new challenge for Spider - Girl, especially if Mary Jane is caught in the middle.