Two features that we'd love to see added to SE:
A log of messages sent through SE (like a "sent" folder)
If this isn't possible, the ability to have an address (like archives@myorg.com) be a recipient automatically to all messages
Ability to change where messages come from. Like when we're sending registration emails, we'd like the emails to not come from the user's primary/personal SE account. For instance when we're contacting our winter development registrants, we'd like the email coming from winterdevelopment@myorg.com. We've tried setting these up as verified emails, but a From dropdown doesn't shown when we're crafting the messages.
It wouldn't be spooked. We could setup all the right DNS records (SPF/DKIM/DMARC) to make sure that the emails from SE are legitimate. Granted this wouldn't work for every domain (like people's gmail), but it would work for all emails from our org's domain, which already has the proper email DNS rules in place for the existing SE email sending.