The extent of my moderation experience has been a few old phpbb forums and a few admittedly large Facebook groups. Let me think it over and I’ll get back to you shortly.
I also wonder if it might benefit from ebooks being separate because authors could post updates about them as theoretically as well as it’d be easier to manage spam.
They shouldn’t have had storage issues, they were never going to host images or communities. They simply were an instance that only federated with nsfw instances so all could be only porn.