Yes, I agree a delete button should be added. As a new user moving from Outlook, I REALLY MISS the delete trash icon that only appears when the mouse is hovering over a message card. Having to click twice is a pain but it's worse when you go to a card at the bottom of the screen, and then when you click up the menu, the delete is at the far end.
This would be very helpful. As others have pointed out, when you have a large number of emails to sort through, having a one-click delete feature makes it so much less painful.
