I have set ups where I tuck into brush and set ups where I set up in the middle of the field. I put PB no more than 10 yards from the blind and no other decoy any farther than 12 steps. Many times I put hen deeks very close to the blind, 5-10 feet. This way if a bird skirts your deeks by 20 yards they're within shooting range.
As far as opening the window, I always try to face away from the sun with the open part of my matrix. If they come in behind I shut the blind and shoot out the little portal windows.