I've used a blind for years to hunt turkeys. They are great. To answer your questions.
1) I only open the windows enough to shoot out of them. I leave the mesh covering most of the windows so I'm hidden, but I have a 360 view.
2) I just wear my camo clothes.
3) I hunt in mine as fast as I can get it set up. I've had turkeys wall right beside my blind in a matter of minutes after setting up. I don't know if you have many coons where you live, but where I'm from if you leave one out for very long the coons will have it shredded.
4) My blind is not really brushed in. I do try to sit up by a couple of trees.

Like I've said, I've had turkeys walk right beside my blind. They are great. When my kids were little we would sit in the blind and play cards while hunting.
I hope this helps.