Many excellent points here. Last year, I released a collection entitled Infestation: A Horror Anthology. The volume consisted of six tales, the first, Infestation, being a sci-fi horror novella in six chapters, about 25,000 words long in total. The remaining five short stories were each between 10,000 and 15,000 words. The total word count for the collection was around 75,000 words or so.

Four out of these six stories I'd previously published on Medium (including Infestation), but two more were exclusive to the volume. :)