Requested feature overview description.
Posting of story based content in general text with markup support.
Why would it be useful?
I believe it is a gap that needs to be filled as there is a big lack of a centralized location for story based content to be shared. I know the e621 site is primarily an image based site, however I simply cannot look past the one useful feature which is sorely lacking from any site, and that's comprehensive and community editable tagging support.
I believe it would be of great benefit to the community to open up support to written artists to archive and source their work with a tagging format that people can add to and help others find the kind of stories that scratches their itch. About the only way stories can be posted at the moment is if they accompany some art, but stories don't get the limelight by themselves.
I would not suggest that the written works should be posted alongside the images, but something like a new posting board for text based content. Stories may be linked as a parent post to an image, as opposed to just being part of the description.
I've had thoughts on future features as well.
Tagging paragraphs or sections of stories. This could help identify stories which cater what a user searches for, as opposed to a singular passing mention.
Translation support. Stories can come from anyplace and it's a shame that many stories cannot be read unless you know the language. Having alternate language support would aid in opening up many new stories to the community.
Download options. Text is fairly easy to convert to other formats. Download support to PDF, epub, rtf, or raw text will allow an easy way to digest things how they want.