mad Idea is very simple. There can be many different ways to realise it, I suppose. But the very simple one is to make it work with snippets. For example I want to make a template for magazine article and have an ability to insert block with reference to another article with link, title and image. I can have there markdown text as a content var, but all the options are provided only by Markdown syntax, so I can not make any custom blocks inside of my content block. My idea is to implement shortcodes, so I would be able to insert something like [article url full] inside of my markdown var, which would reference to snippets/article and implement here some custom vars.