Regarding roost height... my two Marans, if not locked in their coop at night, prefer to roost on a tree branch in the hedgerow. It's 8 FEET off the ground! And they're big birds, not flighty little things. They hop up to the top edge of the compost bin (36" high), then just sort of... flap up there. ("fly" is too elegant a word for what they do.)