Very good detail. More than enough space. Back rooster issue, dog is going to continue to be a weak link. Such a young rooster i would call a cockerel and he is not yet at full potential for whooping chiquaquas. I routinely adult chickens as pairs; 1 rooster to 1 one hen and that is typically more difficult than with more hens. What I do is keep young roosters, in the age interval of 6 to 9 months, away from hens and sometimes isolated from each other. It is roosters of that age that cause most of the difficulties attributed to roosters. Roosters that are older typically are much better around hens, pullets and even chicks. I reccomend setting that rooster up with his own pen and confine him. This will allow you to get females and rear them up. It is possible that by time you are ready to mix the new birds with rooster, he will have mellowed out even with respect to dog. Such roosters that are man-fighters are easy to deal with but some little dogs may not have right stuff to stop aggressive roosters from attacking. In that case you will still have may management options with respect to that rooster, including getting rid of him.