@craigmaloney I may have mentioned this before, and it might be radically different to what you have in mind, but I wrote some software to play RPGs online. No support for rules, though, so more like a grown-up, improvised Choose Your Own Adventure book or something: http://hardcorenarrativist.org/narrows/
It has improved somewhat since the screenshots/screencast but the basic idea and UI are the same.
@craigmaloney There's a feature to read finished stories sort of like a novel. I can send you a sample so you can see how it looks with images and music integrated in the chapters.
Don't expect much from my writing, though, I'm not even a native speaker :-P
Octodon is a nice general purpose instance.