Thank you for this great suggestion! It would certainly add a lot of flexibility to our product suite if our partners could update and manage their own email content. As you know already, we do allow customizing of all the emails (as Martha mentioned in her comment) and we implemented the custom content for emails to provide another step towards this flexibility. That being said, this feature is definitely a long term goal for the Enterprise product suite!
Please keep the feedback coming!
Parker Crawford, Director of Enterprise Product Management