I can't think of any real pros to free ranging other than the romantic aspect of 'happy' / free animals.....and the pragmatic aspect of lower feed costs.
The cons far outweigh the pros for me, I live on a busy 55mph road and have 15 acres of woods that are home to many predators, so mine are confined to a decent sized coop and run that is hawk proof and pretty good against other predators. I live where we get feet of snow for months, so built coop of a size to accommodate weather related confinement. They are provided with vegetation in grazing frames and kitchen and garden scraps, animal protein with homegrown mealworms and kitchen scraps. Egg sales cover the cost of purchased feeds.
Cons:
Poop everywhere, often where you want to walk near the house.
Dead birds in a busy road and due to predation of numerous kinds....dead birds don't lay eggs.
Destruction of food and/or ornamental gardens, I'd rather fence them in than have to fence them out of where I don't want them destroying things.
Egg hunting, can't sell eggs I can't find, free rangers often choose to lay elsewhere than in the coop.
Just my opinion.