One issue that pops up in a number of more thoughtful wizarding school novels and worlds is the question of precisely what happens to magical students who don’t get to go to magic school? Do they remain untrained, seek training elsewhere, or… or what? In Schooled in Magic, most of the potentials do try to get training from hedge witches and suchlike if they can’t get into schools, but what happens if that goes badly?
Sometimes, as the (deliberately) unnamed girl from this story found out, it ends very badly indeed.
Again, this story might become a full novella or novel. Are you interested? Let me know.