Perhaps there are magical elements in the village that are unique and Harry has to deal with some threats to the village while inheriting it. He could find some ancient magic there that is both a power and a burden. Also, the villagers might have their own expectations of him as the new heir, which could lead to various interesting interactions and storylines.
One possible plot could be that Harry Potter, as the new owner of Hogwarts, decides to reform the school's curriculum. He might introduce new magic subjects that were previously overlooked, like ancient rune magic for practical applications.
Perhaps in this fanfiction, Harry inherits Azkaban due to some dark family secret. He then has to deal with the dark forces that have been lurking within the prison walls for centuries. He might find a way to use the prison's own dark magic against Voldemort's remaining followers who are hiding in the shadows.
One possible plot could be that Harry discovers the island is a magical place filled with ancient spells and potions. He might use it as a sanctuary away from the wizarding world's chaos, perhaps to study magic in peace and develop new spells.
In this fanfiction, the island could be a place where Harry's family had some sort of connection in the past. There could be a hidden family legacy there. Harry might find old family artifacts, and through exploring the island, he uncovers more about his family's history and how it ties into the wizarding world as a whole.
In this fanfiction, Harry Potter might face challenges from the existing power structures in the kingdom. However, he would use his Gryffindor courage and the support of his friends. He could reform the kingdom's laws to be more just, as he has seen the importance of equality at Hogwarts. He might also establish a magical academy in the kingdom similar to Hogwarts to train the young generation, which would help to integrate magic into the kingdom's daily life and make it more prosperous.
Obviously, Harry Potter himself is the most important. Then there could be some old villagers who know all the secrets of the village and guide Harry.
Well, perhaps Harry Potter decides to build a village for the magical creatures who are homeless. He might use magic to create little cottages and gardens. He could also set up a school in the village for the young creatures to learn magic in a safe environment.
Well, perhaps in the fanfic, the betrothal is part of a long - forgotten magical pact. Harry, being the hero he is, feels a sense of duty to uphold it. Daphne, on the other hand, is a complex character. She might be initially cold towards Harry but as they face various magical challenges together because of the betrothal, they gradually fall in love. For example, they might have to deal with dark wizards who want to use the betrothal for their own evil purposes.
Some pure - blood supremacist wizards might oppose Harry. They may not like the idea of a half - blood like Harry having so much control over a city and could try to create unrest. Also, there could be some non - magical criminals who target the city because of its new magical elements under Harry's leadership.
In some fanfictions, Harry inheriting a fortune could lead to him having more political power in the wizarding world. He could use this to change laws that are unfair to certain magical creatures or groups. For example, he might fight for the rights of house - elves. He could also use his money to fund research on dark magic prevention, making the wizarding world a safer place.