> All for the initial idea which is so simple that it seems redundant: look as good plain as rendered. (Then what’s the point of rendering it, and in turn what’s the point of a formal syntax instead of the (still existing) ad hoc email and whatnot conventions?)

It's intended to look as good as possible in both mediums. It is not possible for the raw text to look as good as the rendered text and still be easily writeable, because the raw text cannot generate visual hierarchy using font size and weight.

I suspect you know this, but when you say readable raw text seems like a redundant idea, I'm not sure what point you're trying to make.