I suppose by DE you mean diatomaceous earth. DE works great for mite control but don't use it where you live. It is a nasty eye irritant. It is a powder so it might not do much good ridding the roost of mites.
I like wheat straw. It is really cheap and one bale will last months. My coop has a wood floor. Every week or so I throw a layer of straw into the coop and in the adjacent run. The run surface when I first move the tractor starts out grass but in a day or so it's scorched earth. I leave...