Thanks guys. Everyone told me I was nuts not doing a completely enclosed blind, but I've got three on the property already, and that's fine if it's raining. This was conceived as a fair weather blind.
This is a deer's eye view after applying the camo burlap. I used landscape cloth for backing because the burlap let too much light through.
Here's a view from inside:
I ziptie pipe insulation on the top rail for a gun rest. The camo extends above the rail, so when I deploy the rifle, I'm still mostly hidden.