In 'a wish granted fanfiction', it's likely that the central theme is the wish - granting itself. This could lead to interesting character development as the character who had their wish granted may change in many ways. They could become more confident, or perhaps more conflicted. It also might introduce new conflicts in the story, like how the wish affects other characters or the overall balance of the fictional world.
Well, 'a wish granted fanfiction' could be about various things. It might be a story where a character's wish is granted in the context of a particular fandom. For example, in a Harry Potter fanfiction, a student's wish to master a difficult spell might be granted in an unexpected way. It's all about exploring the possibilities within the world of a pre - existing story.
It could be a story that focuses on the concept of wishes being granted in a very specific fan - created universe. Maybe it's a sci - fi fanfiction where a character wishes for a superpower and then has to deal with the consequences of that wish being granted. There are countless ways it can be developed depending on the original source material and the creativity of the author.