Thanks everyone for your replies. We decided to make a new large permanent pen instead of a chicken tractor to ensure their safety, plus we will be able to provide them with more shade. Our soil is all sand and I think some of our dogs would tenaciously try everything to get to the chickens, so we'll just go with buried fence, zap wire, and land mines

Woodland Woman, you are right! We want the chickens to have more vegetation, more room to roam, and I want to be able to see them better from the house. They have already eaten almost all the grass and they've only been in there a month.
Here are some photos of the inside of the coop.
Feeder and nest boxes:
Door to the outside on pulleys (although I saw a link to the automatic door here in the forum and might have to change ours to that one!):
Roosts and poop chute. Four chickens sleep on this top roost, however the buff orpington pictured here, and her bud, the barred rock pictured above, like to roost on the window sill. (The buff orpington was just posing for the camera.)
Outdoor roost: