I read your article about using the Touch Bar for getting through email using the Airmail app. I use that app too. To get in and out of my email as quickly as possible I have set up a few finger gestures in Better Touch Tool. It’s faster than reaching out for the Touch Bar I think and becomes second nature after a few days.
For example on the track pad I have:
3 Finger Swipe Down: Archive an Email
3 Finger Swipe Up: Delete an Email
3 Finger Tap: New Email
3 Finger Swipe Right: Forward an Email
3 Finger Swipe Left: Reply an Email