Wow.. that hit the concept on the head. Definitely love the idea, quite a lot actually. I think this would be made into a 'Serious" type of game that can actually help people out with stress. Love it. The only thing honestly is the visual, having something else that can be calming would be nice, change of backgrounds when you get to a certain point or circle scaling up and down when you get to the breathing part, etc.
Thanks this was pleasant!