I’ve been working on a few email apps with the saas company I am employed by. My job is mainly app testing, we found that there are not a lot of great editors out there for writing normal emails (ie, not newsletters).
Typically using something like tinymce as a text editor for an email app can mess with delivery rate - example:
Message only has text/html MIME parts
You should also include a text version of your message (text/plain)
It would be really great if you built a text editor specifically for writing normal emails built for perfect delivery.
Just an idea