You could write about a magical adventure in a fantasy world. It's always fun to create new creatures and lands.
How about a story based on a real-life event but with a fictional twist? It adds an interesting layer to the narrative. For example, a story about a historical event but with a character who has supernatural abilities.
A short story about a character's journey of self-discovery can be quite engaging. Maybe they face challenges that force them to look within and grow.