Another concept could be a crossover of the two universes' technologies and magic. Maybe the Stormtroopers are trying to harness the power of magic for their own purposes, like creating more powerful weapons or defenses. And the wizards are both intrigued and worried about this new development.
There could also be a story where a group of Harry Potter characters find themselves in the Star Wars universe among the Stormtroopers. They have to figure out how to get back home while also dealing with the different cultures and rules in the Star Wars world. They might use their magic in unexpected ways that shock the Stormtroopers.
Some fanfictions in Harry Potter 2 might play with the idea of the basilisk having different powers or weaknesses. It could also explore the idea of a hidden connection between Ginny and the Chamber of Secrets that goes beyond what was in the original story. There might be fanfictions that change the role of certain characters, like making Neville a more central figure in solving the mystery of the Chamber.
One interesting concept could be a shapeshifter who uses their ability to infiltrate the Death Eaters. They could change their appearance to gather intelligence and help the Order of the Phoenix.
Well, in some Harry Potter starship fanfiction, there might be the idea of using Patronuses as a form of energy source for the starship. Since Patronuses are powerful positive magical manifestations, they could potentially power up the ship's engines. Also, there could be a story where the starship has to travel through different magical dimensions, like the ones that might be related to the Forbidden Forest's hidden areas, and the crew has to use their knowledge of Hogwarts magic to survive.
Well, one interesting concept could be alternate universes. For example, a fanfiction might explore what would happen if Harry was sorted into Slytherin instead of Gryffindor. Another concept could be different relationships between characters. Maybe a fanfic delves into a romantic relationship between two characters who were just friends in the original series. Also, some fanfictions explore the backstories of minor characters in more depth, like Neville's family history in a more detailed way.
Another concept is that the portraits have emotions and desires that are more complex than what is shown in the original books. They might long to be free from their frames, or they could form relationships with the living characters. Some portraits could even fall in love with a wizard or witch passing by, leading to all sorts of interesting and sometimes comical situations.
Some fanfictions play with the concept of character backstories. They might give more detailed and different origin stories for the main characters. For example, they could explore what if Harry Potter had a different family background that affected his character in new ways. Another concept is the expansion of the Forbidden Forest. There could be undiscovered areas with new and dangerous magical creatures. And there are also fanfictions that focus on the post - war wizarding world, showing how the characters are rebuilding and dealing with the aftermath of the great battle.
Well, some fanfictions in this category might focus on the moral implications. For example, how characters who oppose slavery in the 'Harry Potter' universe fight against it. It could also be about the redemption of those who might be involved in or benefit from the slavery system, showing their journey to realizing the wrongness of it.
One interesting concept could be alternate universes where the mates have different relationships. For example, a story where Harry Potter's mate is from a different house and they have to overcome house rivalries. Another could be exploring different magical abilities that the mates possess together, like a combined spell - casting that is unique to their bond.
In this type of fanfiction, an interesting aspect could be how elemental magic affects the wizarding world's ecosystem. For instance, if earth elementals start to act up, it could cause earthquakes in wizarding areas. And the training of young wizards in elemental magic could be different from the regular magic taught at Hogwarts. They might have to go on special quests to find their elemental affinity, like traveling to a volcano to test their connection with the fire element.
One interesting concept could be a new take on the power dynamics within the wizarding world. Maybe the 'kingpin' character has a different view on magic and how it should be used, challenging the traditional Hogwarts teachings.