For my own use, I tend to go markdown for everything. Then it becomes either a blog post with hugo, or an email with markdown here (a browser and mail client extension to turn your markdown into html in a rich text field, or in an email), or a html doc.
For work, when I have no choice, I use office365. It sucks though, it's not even fully compatible with using the desktop versions of the apps (size of elements, positioning will always be slightly off)