Another theme is mystery. The apothecary often gets involved in solving various mysteries, whether it's about a strange illness or a hidden secret in the town. In fanfics, this mystery element is often expanded upon. For example, some fanfics create complex mysteries that involve multiple characters and different locations. It adds more depth to the story.
Another great one is 'The Apothecary and the Lost Artifacts'. In this fanfic, the apothecary is on a quest to find some ancient artifacts that are related to her field. It has a great blend of adventure and the unique apothecary elements from the original work.