There’s a good chance I’m going to get branded as a techie-luddite (a
contradiction in terms if there ever was one) for the recommendation I’m
about to make.
I believe that 90% of your outgoing email should be in plain text format. Maybe more.
Aside from a collection of technical reasons I’ll get to in a minute,
it’s simple really: you want people to focus on what you have to say, not
how it looks. Lots of formatting, backgrounds, highlighting and using
many different fonts and styles are all things that distract from your
words. They’re more about making your message “pretty” to look at, and
rarely add value to your ideas.
I’m not saying never use HTML (or Rich Text) email, but I am
saying default to using plain text and only use HTML email when you
really need to, which is actually pretty rare.