I've just switched to mu4e. It's unbelievably great, thank you everyone
who's recommended it over the years.

However, I would like to compose my replies in org-mode and send them out
as HTML.  I guess the older tools for doing this are officially deprecated.
Nonetheless, does anyone use them? Would you be willing to share your
workflow, and thoughts about what pain points you still have?? I see John
K. has written some cool posts about, e.g., sending headings out, but not
about org-ifying the compose buffer.

Thank you!
Matt