I add holes at the apex that can be easily blocked over during the winter to dampen down the ventilation a bit when it's cold, which is also when the smell dies down with somewhat less need for venilation. I would frame the coop, envelope with hardware cloth, add siding. I'd focus the insulation effort on the inner coop where they will be roosting. I'd make it off the ground with the entry down low, in the floor so they come in from underneath, this will conserve heat via thermocline. I'd make the studs of the inner coop close enough to place foam bats in and use spray foam to seal up the gaps around the edges, then come back and trim before adding covering. this is best done in the summer when it's easy to provide ventilation while it's all off gassing. anywhere there is foam it must be covered with something they can not peck through or they will get into the foam and eat it. I would think that the outer walls of the coop would not need to be insulated as chickens can handle very cold day time temps as long as they are not exposed to draft. my chickens seem to lay more during the winter since I have taken efforts to keep them warmer. there will always be a trade off between warmth and ventilation, you will need to keep an eye on it, it's not worth toxing your birds with amonia to keep them "comfortable".
