Well, in some fanfictions, there are plotlines about the Marauders getting involved in some sort of mystery at Hogwarts that is deeper than the normal school drama. For example, they might uncover a dark secret about one of the teachers or a hidden part of the castle. This could lead to them having to use their combined skills and friendship to solve the problem and keep the school safe.
Some fanfictions might have a plotline where the Marauders are faced with a threat from outside the school, like a group of dark wizards targeting them specifically. This could show how they grow from being just mischievous students to brave young wizards ready to fight for their lives and the lives of their friends. It could also explore their relationships more deeply, as they rely on each other in the face of danger.
One interesting plotline could be the identity of the masked marauders. Are they related to the original Marauders? Maybe they are descendants with a new mission. Another could be their interactions with Harry and his friends. Do they help or hinder Harry in his fight against Voldemort? It could also be about the secrets they hold that are related to Hogwarts' past, which could be a major factor in the story.
Maybe Harry finds himself in a situation where he has to team up with the Marauders to fight a common enemy that was previously unknown in the original Potter story. This would create a whole new dynamic and show how different generations of Hogwarts students can work together.
Perhaps a plotline where the Marauders' spirits or echoes are awakened in Harry's time at Hogwarts. They start guiding him in his fight against Voldemort. They teach him spells and strategies that they used during their own battles against the Dark Arts. This would give Harry an edge and also create some really heartwarming and funny interactions as he tries to keep their presence a secret from his friends.
A great plotline in such fanfics is when Harry has to deal with the time - travel paradoxes. Since he's in the Marauders era, any change he makes could have a huge impact on his own future. He might be hesitant to do too much at first. Also, his relationships with the Marauders are fascinating. He could become like a mentor figure to them in some ways, teaching them things he learned from Dumbledore. And the whole idea of him being in a world where Voldemort is still rising but in a different stage is full of potential for exciting story development.
One interesting plotline could be Harry trying to prevent the death of his parents. He might use his knowledge from the future to change certain events. For example, he could try to stop Voldemort's rise to power earlier in the Marauders' time.
Well, in some 'Harry goes to Marauders time' fanfictions, a great plotline is Harry trying to prevent certain tragedies. He might attempt to stop the betrayal of one of the Marauders, knowing how it will all end in his own time. Also, his relationship with Lily and James could be a major part of the story. He could be the one to give them some advice that changes their fate, like how to better protect themselves from Voldemort.
One interesting plotline could be how the Marauders deal with Harry's magic emerging at an early age. Since they were quite mischievous themselves, they might have some unique ways of guiding him. For example, Sirius could teach Harry how to transform into his animagus form earlier than in the original story.
Perhaps a plotline where Hermione has to solve a mystery that the Marauders were involved in. The Marauders might have left behind some clues that only Hermione, with her sharp intellect and research skills, can decipher. This could bring her closer to understanding their true nature and the secrets of their time at Hogwarts.
One scenario could be the Marauders reading a fanfiction where they survive and get to meet Harry as adults. They might be amused or even a bit critical of how the author portrays them. Another could be them reading a time - travel fanfiction where they interact with their future selves. It would be a really strange experience for them to see how others imagine their future actions and personalities.
Another plotline could involve Petunia getting involved in one of the Marauders' adventures by accident. Maybe she stumbles upon them while they are exploring a secret part of Hogwarts and has to work with them to get out of a tricky situation.