Thanks for the feedback. Added the screenshot. Not familiar with writer-computer. Will take a look.
MDedit gives you explicit Edit / Split / Preview modes which is useful when checking what some Markdown syntax loooks like. MDedit allows exporting rendered HTML, PNG, print-to-PDF, individual tables as CSV, and diagrams as SVG. HTML can embed local assets. I did not see those in my (admittedly skimpy) review of writer.