I want to maximize my marketing emails to get delivered, so I'll use three audit tools to try to get an idea of whats happening.
See important results from each below:
2.3 EMPTY_MESSAGE Message appears to have no textual parts and no Subject: text
1.0 MIME_NO_TEXT No (properly identified) text body parts
HTML and text parts are different
Make sure your TEXT version looks similar as the text inserted in your HTML version
Nothing particularly important.