Sent and received emails often have common themes and so for improved efficiency and productivity these emails should be organized into email folders with self-documenting titles.
Currently the Canvas messaging utility ("Inbox") does not allow users to create organizational folders.
Every email utility that I have worked with, including the Blackboard mail utility, allows users to create folders. Hopefully Canvas will one day in the near future allow its users to create folders in their email.
This email folder feature request is closely tied to the feature request that I recently made in which I requested that each Canvas course have its own "Inbox" in its unique Course Navigation Panel. If the Canvas "Inbox" remains in the Global Navigation Field then the self documenting labels for folders would have to include the course title and section number of the Canvas course (or the course's Canvas nickname).
Added to Theme
Improved UI Controls and Usability - Additional filtering and view options Theme Status: Identified