Hey Paul here is some info from my experience here in Idaho with the breed.
Our set up:
coop is in a empty horse stall we had they have the corral, and 5 acres of pasture to run around in, We put a nest box on the ground as they didn't seem to like the ladder to get up to the perches, but they do like the new ramps we added so are choosing to use those.
2 cornish x hens
4 Barred Rock hens 1 Rooster
2 Rhode Island Red pullets 1 cockrel
2 Ducks
2 Brown Leghorn hens
2 White Leghor hens
2 Buff Orpingtons
We got 10 cornish x.we have a mixed flock we started in April, we processed the roosters and any aggressive hens at 2 months, but we kept 2 hens that integrated well with the flock, they are feed the same feed our egg layers are and are out free ranging with them. Our Barred Rock Rooster is trying to patiently wait for them to mature as he seems to like the cornish x, they are his favorites. Trick to keeping them active is put them in a mixed flock and on the egg layers feed they grow slightly slower but stay healthier. Will let you know how it goes when they start laying. So far only ones we have lost are the ones we processed. They have been out in the coop and free ranging with the others since we brought them home.
Feed we do fermented feed of 3*1 grains2 times a day, they forage during the day, when hens come in to lay we put down 1-2 cups of Laying crumbles for them
PD put a pie plate or something down for them when it's really hot and they will go cool off in it and make sure they have plenty of access to water for drinking. we put a few dishes around the area where they free range too.
They all get scraps from the garden so if they get in the garden we put them on lock down for the day and they don't get them the next day, they have learned real quick to stay out of the garden, the wild birds are another story though. they love Watermelon, cantaloup, sugar snap peas,cucumbers, and the peelings from potatoes. Tomato is more like corn for us though so we haven't given them that again
