Have been working with HTML in decades and still it's quicker to write markdown for simple documents. Now if you'd have some middle ground that would be nice. And actually there are already things like Githubs Markdown which has more features, you can embed mermaid etc. Or you'd use something like MDX (which readme.com is using internally) where you mix in components when needed - those could even be based on something like bootstrap because you might like having cards and layouts. Now the only thing missing is support in the interface. Plain HTML can already be rendered, adding a more capable Markdown shouldn't be too hard.