> Markdown in an of itself isn’t powerful enough to satisfy the simple monkey brained developer like me who is only satisfied when the site looks good enough™.

Well, indeed, Markdown is an inadequate tool for that. Let the author use more powerful tools, be it HTML, LaTeX, SVG, etc.

Markdown is fine for its intended purpose: very light formatting, very simple header structure. If I were not that lazy, i would come up with something opposite to CommonMark, some MarkDownDown, that does away with alternative ways to format things, most escaping, and most advanced syntax. The goal would be to have an easy-to-implement, unambiguous, safe and simple subset good for use anywhere. Intentionally limited.

(For daily use I prefer Org Mode, due to its vastly superior support in my preferred editor.)

I use a horrific mix of:

• Markdown (most of my notes these days, supplanting my previous use of plaintext.)

• Single-file HTML (when my use case for fancy documents exceeds markdown's limits. While you can embed HTML into markdown, renderers vary in what they allow or sanitize, and vary in how you can (ab)use style tags. I've even taken to looking up CSS rules for printed documents, since my intended target is often pdfs or actual print at that point. Occasionally, JavaScript!)

• Google docs (Android phone nonsense!)

I'd mutter something about "using the right tool for the right job", but that's probably giving myself too much credit.

Exactly. I write my own notes in markdown, it works with or without a viewer app. I am not even sure if there is a better alternative. This format is good enough for most of the casual and semi serious use cases