I have spent quite a while researching coops and actually I've already built mine. Most of the tractors I've seen with attached runs have a fixed position run that then required moving both the coop and the run in order to get to new 'foraging' areas. Would a circular coop, with a run attached to some kind of a hoop, thus allowing you to just rotate the run around the coop, allowing for 360 degree rotation be feasible I've seen fixed coops with multiple attached run areas allowing access at different times of year. But I'm thinking of something much smaller in scale that would be movable. Just a thought for you engineering types. Hope this is a little clearer than mud.