There is a link on each email in the footer. Would using this on your site work? Seems to for me. You can get it by sending a test email to yourself.
There are several good open-source editors out there. One of the best that is designed for this environment is CKeditor. I have used it for years in the Joomla environment. It is straight-forward to integrate into a site. Maybe you could look at it.
Is there a reason you do not like to add yourself to the list you select?