Hi Chalky and welcome to the forum. Amazing quest you have. We have a problem here keeping the fluffier breeds cool in Summer and one keeper I have contacted (she has 400 chickens plus numerous rabbits) keeps all hers in a large (600 square metres floor) stone barn and uses a big mobile industrial fan in Summer to move the air around. How do you cope in Greece with the heat?
Because of all the predators here, the biggest problem being stray dogs, we keep ours in a 6 foot high chicken wire enclosure. The enclosure is subdivided to form smaller areas and each flock has a coop and run within one of these areas. The walkways between are used as a run for Transylvanian Naked Neck hens -they have no cockerel so no problems with fighting through the fence, although occasionally there will be a minor scuffle between hens in the sub-enclosures.