First,
This is the best resource for anything "chicken". I also recommend you get a book, Chickens for Dummies, or Storeys guide to raising chickens. I have the latter and it is a wealth of information.
I'm not nearby, but I recommend much more ventilation otherwise I'm afraid you'll have a small oven in your yard for those chickens with all that aluminum siding and the summer heat that's right around the corner.
I have sand in my covered run and just bare dirt in my open run. The girls like both. My coop has 3-4 inches of pine shavings on top of linoleum-covered plywood flooring.
I have 2 roosts, the first being about 12-14 inches off the floor of the coop. They just hop up there now, but until they were full grown I had a little 2-rung ladder for them.
I can't tell what kind of wire your run is enclosed with, but know that "chicken-wire" only keeps chickens in - it will not keep predators out.
All in all you have a good little set up. What are the dimensions of your coop? Make sure your chickens have plenty of room. I found out this winter that having the BARE MINIMUM of square footage caused some "cabin fever" - in other words, the girls started featherplucking each other. Situation remedied with an addition of about 100sq ft of outside uncovered run.
Keep posting and asking questions!