This would be especially useful for creating rules. To create rules you have to grab info from messages (subject, sender info etc) and without the ability to create tabs, you have to constantly go back and forth which can be tedius.
Everyone using this app would benefit from the ability to change fonts when working on mobile. It goes without saying the value this would add as many prefer to maintain their own styles without deviating should they be working away from the offic...
Include ability to right-click and copy an attachment to paste it somewhere else. Include ability to right-click and copy or drag and drop the email address that is in the "To" or "CC" or "BCC" line into the body of the email. Allow to right-click...