One idea could be that they face challenges from the wizarding community who don't understand their relationship. Another could be them exploring new magical abilities together as a married couple. Maybe they could also go on adventures to discover ancient magic secrets that are related to their combined family lineages.
A really interesting plot could be that Molly has a special power or ability that she has to keep hidden. But when she and Captain James get married, she has to reveal it to him. This creates a whole new dynamic in their relationship. They then have to figure out how to use her power for the good of their community or ship or whatever the setting is. There could also be a sub - plot where an enemy tries to use Molly's power against them, and they have to fight to protect their new - found happiness and the future of their relationship.
Another plot could be that they are married in an alternate universe where their backstories are different. Maybe Voldemort was never as consumed by dark magic from the start. Harry and Voldemort could then discover that they have a deeper connection than they thought, and their marriage could be a journey of self - discovery for both of them, as they explore their relationship in a world that is both familiar and yet very different from the one they knew in the original story.
One idea could be that they start a new magical school together. Since Gabrielle has her own magical abilities and Harry has so much knowledge from his Hogwarts days, they combine their resources to create a school that focuses on both traditional and unique magical teachings.
One idea could be them exploring different magical creatures together as a married couple. They might go on a journey to find a rare and endangered magical creature and work towards its conservation.
Maybe in the fanfiction, Harry's marriage is a political move within the wizarding world. He marries someone from an important pure - blood family to help unite different factions. This could lead to a lot of drama as he has to deal with the politics and also keep his own values intact.
A possible plot is Molly Hooper being drawn into a world of dark magic while trying to solve a strange death at a historical site. It could involve her trying to figure out how the victim was involved with a secret occult group. Or, she could be targeted by a serial killer who has a fascination with her work in the morgue, and she has to use her wits to outsmart the killer. She might also find herself in a situation where she has to choose between her loyalty to Sherlock and her own safety in this dark fanfiction scenario.
One plot idea could be a time - travel fanfiction where they get married in an alternate timeline. Maybe Harry accidentally activates a time - turning device and ends up in a world where he, Ginny and Hermione all decide to have a triple wedding for some magical reason. Another could be a post - war fanfiction where they get married as a symbol of new beginnings and unity among the wizarding community. For example, their weddings could be grand events that bring together all the different houses and factions that were once divided during the war.
Another plot could involve the main character in the fanfiction realizing that they got married too young and now they are having second thoughts. This could lead to a series of self - discovery and relationship - testing events. For example, they might meet someone new who makes them question their marriage, but in the end, they realize the value of their relationship.
One idea could be them having to deal with the reactions of their friends and family. For example, Harry's friends from Gryffindor might be initially shocked but then come to accept it as they see how happy Draco and Harry are together. Another plot could involve them facing some sort of magical mystery or threat that only their combined skills can solve, which also strengthens their bond as a married couple.
One idea could be that they face opposition from some in the wizarding world who still hold onto the traditional views of pure - blood and half - blood relationships. They then have to fight to prove that their love is stronger than these archaic beliefs. Another plot could involve them having to deal with a new dark threat while also planning their wedding, adding a lot of tension and drama to the story.