In Clannad fanfiction, a common concept is the expansion of relationships. There might be fanfictions that develop the friendship between Nagisa and Kyou in more detail. Or perhaps show how the relationship between Tomoya and his father could have been mended in a different way. Some might also explore the idea of characters having superpowers or special abilities in a Clannad - like setting, which would be a really unique take on the original story.
One idea could be a crossover with a magical girl anime like Sailor Moon. Clannad characters could find themselves in a world where they have to fight alongside the Sailor Scouts against a common enemy. Maybe Nagisa discovers she has latent magical powers and has to learn to control them with the help of Usagi.
In Harry Potter and Clannad fanfiction, a great crossover idea is the exchange of character traits. Maybe some of the Clannad characters could be sorted into Hogwarts houses based on their personalities. And vice versa, the Hogwarts students could learn about the strong family and friendship bonds in Clannad. It could also involve a plot where a powerful Clannad character has to deal with the dark magic threats in the Harry Potter universe. This would create a whole new set of challenges and adventures for both sets of characters.
Perhaps a plot where the magic that exists in the Clannad world is more fully understood and harnessed by the characters. This could lead to new ways of solving the problems they face, such as Nagisa's health issues. Also, a story about the characters in a post - Clannad world, how they are building their new lives and families.
In the backrooms fanfiction, the concept of the 'safe rooms' is really cool. These are areas within the backrooms where the entities don't seem to go or where the environment is a bit more stable. It gives the characters a brief respite from the constant danger and allows for some interesting plot developments as they plan their next moves.
One interesting concept is exploring different cursed techniques for the characters. For example, in some JJK fanfictions, Yuuji might have a cursed technique that allows him to communicate with the souls of the dead in a more detailed way. Another concept could be alternate universes where the characters have different relationships or roles. In some fanfictions, Megumi could be the main villain instead of an ally, which completely changes the dynamic of the story.
One interesting concept could be new micro - games. For example, a fanfiction might introduce a micro - game where the character has to dodge falling musical notes in a rhythm - based challenge. This would add a new and unique gameplay element to the Warioware universe.
One interesting concept could be alternate universes where the Planeswalkers have different alignments or abilities. For example, a fanfiction might explore a world where Jace Beleren is a villain instead of a hero. Another concept could be the exploration of the backstories of minor characters in the MTG lore. In some fanfictions, these characters are given more depth and their own story arcs that are not fully explored in the official lore. Also, there are fanfictions that focus on the relationships between different races in the MTG universe, like how elves and humans interact in a more detailed and unique way compared to the official stories.
Some interesting concepts in MJ fanfiction are those that re - imagine his concerts. For example, a fanfiction could describe a concert where he uses holographic technology in a way that was never possible during his lifetime. There are also concepts like exploring his family life in a more fictional and detailed way, showing his interactions with his siblings and parents in made - up scenarios that give new perspectives on his personal life.
One interesting concept could be exploring different character backstories that were not fully developed in the original. For example, delving deeper into a minor character's family history and how it ties into the overall bloodline theme. Another could be imagining alternate bloodline inheritances that change the power dynamics in the story.
The idea of the entities is also captivating. These are often otherworldly creatures that inhabit the backrooms. They can range from human - like but distorted figures to completely unrecognizable and terrifying beings. Their behavior and how they interact with the 'explorers' in the fanfiction add a lot of suspense.