There could be a story focused on the relationships that form after the war. For example, Neville and Luna might start a magical plant research project together, and their friendship could deepen into something more romantic over time as they work side by side.
One interesting storyline could be how the wizarding world rebuilds. For example, Hogwarts might need a lot of repairs after the war. The characters could be involved in restoring the castle, classrooms, and magical artifacts.
Definitely Harry, Ron, and Hermione. They were the central characters during the war and would likely continue to be important in the post - war stories. They would be using their skills and experiences to shape the new wizarding world.
It could be Ron. Maybe he starts to feel that Harry has changed too much after the war and is no longer the friend he once knew. He might be influenced by outside forces or his own insecurities. Another possibility is Hermione. If she gets too involved in the new Ministry politics and starts to believe that Harry's actions are not in line with the new wizarding order, she could turn on him.
I really like 'Eclipse'. It focuses on the rebuilding of Hogwarts and how the students and teachers are trying to move forward. It has some really interesting new relationships and character developments that are quite in line with the original Potterverse feel.
There are quite a few. 'Rebuilding the Wizarding World - After the War' is a fanfic that details the efforts of Harry and his friends to fix all the damage caused by the war. It has great descriptions of the rebuilding process. 'Harry Potter: Post - War Revelations' is a fanfic that uncovers some secrets that were buried during the war, which is quite exciting. And 'The After - War Journeys of the Golden Trio' focuses on the adventures and growth of Harry, Hermione, and Ron as they move forward in a post - war world.
Perhaps Harry meets magical creatures that are rarely seen by wizards. Since he is out exploring after the war, he might stumble upon a group of centaurs who have their own unique wisdom about magic and the future. He could also encounter veelas, and through his interactions with them, learn more about the different cultures within the magical world. There's also a chance he meets other young wizards who are on their own adventures, and they form a sort of traveling group together.
In such a fanfiction, Harry might initially struggle with his blindness. Ginny, being the strong - willed character she is, would encourage him to not let it hold him back. There could be a lot of emotional moments between them, like when Harry first realizes he can no longer see Ginny's beautiful face. Ginny, on the other hand, would assure him that their love is not based on sight. They might also encounter difficulties from the wizarding society that doesn't fully understand how to deal with a war - hero - turned - disabled, but they would face it all together.
His character would likely become more introspective. Without his friends always around, he'd have to face his inner thoughts and feelings. He might become more self - reliant and learn to trust his own judgment even more.
They often show characters like Harry becoming more of a mentor. He has been through so much in the war, and now he can pass on his knowledge and experiences to the younger students at Hogwarts.