Markdown, both ways
Never lift your hands off the keyboard. Write in plain Markdown, or in a more visual view where the same shortcuts still work.
Markdown mode swaps the page for its own source, so you can edit the raw text directly and switch back with the caret still where you left it. In the visual view the same syntax works as you type: ## for a heading, - for a list, > for a quote. Headings, lists, checklists, tables, images and emphasis all survive the trip in both directions.