I wonder what kind of peminat Fiction to write...

Well, if you're a new peminat fiction author, I'd suggest picking the sumber material you're most familiar with, and Penulisan about it in canon style. It's simpler than alternate character interpretations, OCs, AUs, and anything else deviating (radically atau otherwise) from the original source. It's also likely to garner less hate, even if it isn't incredibly original. Just don't rip off an existing episode.