(my hope is to come up with some sort of "free range" scenario - more like a very large extended run that doesn't have a top (more like a fenced area), attached to the run they have now.
Just scared to death of hawks, etc.
My chicken run is not covered, in terms of a roof, but I stretched out light weight bird netting across the chicken run. In 3+ years of use, I have had no aerial attacks. And I live on a lake with hawks and Bald Eagles overhead all the time. So, I consider the use of bird netting as a success.
Amazon has all kinds and sizes of bird netting. I get my netting local from our Fleet store and a 13X13 foot net costs me about $8.00.
As to free ranging, I don't let my chickens free range because of the hawks and Bald Eagles overhead all the time. But I do bring the free range to my chicken run. All my fresh grass clippings, leaves, weeds pulled from the gardens, etc... gets tossed into my chicken run. My chickens are plenty happy and stay outside all day scratching and pecking through everything looking for bugs and worms to eat. Plus, they are safe under the bird netting.