This. The larger it gets the harder it is to see out of especially if only one person is using it.

I put mobile home windows in mine. Cost about $50 a piece so consider that.

Horse Stall mat on the floor.

Skip the office chair they make a ton of noise. I have bought several nice blind chairs cheap after season sales... leave them at the camp house and you take it with you. I also leave a metal folding chair in the house just-in-case. I use a Banded Swivel blind chair most of the time. Plenty comfortable but not enough you are going to fall asleep in it. I'm out there to hunt so that isn't an issue.