Looks like fun. Hoping you get a great hatch rate. I only use broody hens to hatch. Incubators seem so complicated to me. Wishing you the best of luck.
I know your bantam Cochin roosters weren't long lived, but I always want to talk you back into more because they are my absolute favorite little boys. Confident, and quirky. My kind of guys. I'm partial to mottled and calico.
I don't put up with any forward behaviors out of my cockerel or roosters. As a kid I was terrorized by an aggressive leghorn rooster, and I swore never again would I live with that kind of fear. I don't handle my boys. I think it takes a certain type of smart cockerel to stay friendly and not...
I personally would just feed a ration formulated for waterfowl, and a separate bowl of oyster shells for the calcium needs, and stop all the extra stuff which will unbalance her diet.
Make pen outside next to wherever she's going to live. The cooler temps aren't an issue. I'd be more concerned in warm weather with flies about. Chickens are pretty cold hardy, and good at healing. It will be less stressful for her to be near the other birds.