If I build one, it will be on the back of a large storage shed, so it could be more "rustic". Your design looks very good. I need to consider drainage off the roof. This year's El Nino compels me to do this. In my case, a crushed rock layer underneath would help, but the shed is on a hilltop and that should help considerably. The property owner gave me a green light. He heats his house mostly with wood using an efficient stove, and the house is only about 80 yards away from all the split firewood. My logs will save him at least $400 this year on his heating bill.
This thread is a complete winner. Two thumbs up!