Image not displaying in email
I had this same problem few days back. Try to Inspect that broken Images, your Image might have source like this: src="https://ci4.googleusercontent.com/proxy/a0ulmqxF3B*******************************************gMzBa5MRdHDhrBXYc8KaMYIvFZ2HAf3P_lOwFrg=s0-d-e1-ft#http://yoursite/logo.png"

So if you are trying to send email from your local then probably they did not get cached by some google service because probably google can't access your local, try access.log for any issues.
Some other are also facing the same problem: 
https://productforums.google.com/forum/#!topic/gmail/q47KoUYQXPw

this problem still persists on my local it has nothing to do with mime mail, or any other module, in fact I was able to send emails with images using only print-email- module try this https://www.drupal.org/project/print

Hope this helps you. 
al
PS: If nothing helps try to send mail form live or your development site, you won't face this problem there, because there problem here is google not given access to your images at local machine.