You might do well watching the
Chickens at Polyface Farms video on YouTube. He discusses raising broilers in a tractor, the proper bird-to-tractor ratio, and shows moving the tractor easily. It is, by far, the best video on this topic that I've seen. I'm not sure how large your yard is, but he discusses the idea for backyard chickens, too.
One thing to remember is that everything I've ready says the broilers produce a massively larger amount of poop versus the layers. I'm not sure I would use deep litter for this method or keep it cleaner. I hear using fermented feed drastically reduces the small of their poop, but also decreases it somewhat, too. For substrates, you can use most things you mentioned. I would avoid saw
dust, although wood
chips from a router would be ok. Also, avoid shredded paper unless you know it's acid free and there is no ink on it. A lot of ink is toxic to animals.
If you do not do the deep litter method, use the washed sand. Ideally, the river sand is the best. I believe it's sized between the washed sand and the course sand. It will help the poop conglomerate and make it really easy to use a typical kitty litter scoop to clean with.