When we were starting out, we believed that old-fashioned breeds of chickens would do better on old-fashioned farms. A lot of people believe this. The idea is that heritage breeds are best, while modern commercial breeds are suitable only for factory farming.
Alas, that's not how it works. For starters, there has always been a distinction between show birds (which are supposed to look pretty) and utility birds (which are supposed to turn a profit through their meat or eggs). Never the twain shall meet. Once heritage breeds were supplanted by modern hybrids, that was the end of the heritage utility breeds! You've basically got a bunch of low-producing show birds on the one hand, and high-producing modern hybrids on the other. The middle range, with some exceptions, has gone extinct.
And even utility breeds of yesteryear are nothing to write home about. I did extensive work with California Grays and Rowley New Hampshires, both of which were cutting-edge in the Fifties, but modern hybrids ran rings around them in our hyper-old-fashioned pastured environment. Hmmmm...
In fact, the hybrids are just better, period. They grow fast and have low mortality. The egg-type hens lay huge numbers of high-quality eggs, while the broiler produce enormous amounts of high-quality meat compared to the heritage breeds.
Last time I did the math, I figured that, to sell heritage broilers instead of modern Cornish Cross broilers, I'd have to charge three times as much to make the same money. Not only were there no takers, but I myself was far from convinced that the old-timey birds were worth even the same price per pound.
So my advice is the same as always: test, test, test. We tried everything, and settled on what worked for us. The things you're told and the things that work are never the same things, so you have to test.
I live in Alaska and also have fox, mink, hawks. Thus far this year we have had no losses of our chickens, Just a few vegetables being trampled by moose.