Sending a rating by email

Hi,
I would like to add images to my e-mails. I want my customers to vote by clicking on the images (stars). 

The EmailTemplate module uses a Bootstrap RTE that doesn't allow me to add widgets or images directly from the modeler. I can only upload images from my computer, but that doesn't give me the option to add a microflow to it (to store the ratings).

I've tried using the url of the images, but that still doesn't give me the option to add a microflow, because the modeler only shows the html body as the widget "Bootstrap RTE"

Any suggestions?