I get the desire for WYSIWYG HTML editing. I used FrontPage back in the 90s, including for exactly the same purpose as Blue here. Unfortunately WYSIWYG HTML editing has just never been that good, and likely never will be, for a whole bunch of reasons.
Markdown is the best solution IMO. Easy to pick up, fast and efficient to write and edit (unless you're doing tables or something), generally simple and predictable, and supported in many environments. You need the infrastructure that will convert it to HTML but it's so widely used that there are a zillion tools and libraries for that.