Hey. This drives me crazy...having multiple Airmail windows open and trying to navigate between them. I know I can do this using Ctrl+Airmail icon in the dock, but should be easier!
For example, if I have one received message open in it's own window as a reference point, Airmail open and a couple of draft emails open, switching between each one is hard work. It would really help me if all Airmail windows had shortcuts on them to other open Airmail windows. I find I am constantly moving and resizing windows so I can find or easily reference each one I have open.