Since haxdoc was implemented I got some ideas about more lightweight approach to how things could be done, but the main objective is to get the data format right, this is a purely data transform issue.
So the actionable steps I suggest would be to define a sensible data format, see how much work would be needed to fix nim doc to operate with it instead. I'm writing from the phone now, so this is just a general direction, I will put more details later on today.