EPA stoves need more draft than stoves of yore. If that is what you are comparing chimney layouts to, be sure you are also comparing like stoves... and like houses. A leaky shack with a rusty 4ft pipe on an old Ashley tin can stove is not on the same planet as your air tight house and a modern stove. Cram a cheap piece of pipe in the top of the flue, try dry wood, and do this when the temps are at least below 50. The stove should respond briskly. If not, then go searching for the mouse nest in the air passages. And give your wife a hug. She is correct, we are nuts. Helping people can be an addiction, but there are worse things in life.