Prescript: I am by no means a programmer, and input to follow is likely useless.
Have you looked at Markdown plugins that otherwise align with what you are looking for to see if there are usable approaches to be adopted? Or maybe even contribute a PR to one of those projects for Asciioc support?
In any case, I recently fell in love with Asciioc and selfishly hope you are successful!
I went to the Stranger Things popup in Vegas. Not gonna lie, I had a good time. It was like an amusement park exhibit with the classic gift shop at the end, but the prices didn't seem inflated. If I was interested in buying merch, I'd rather go to to one of these than just order it online. I'm not saying it will be successful, but I don't hate them for trying it.
And, yes, they did sell DVD boxed sets.