Jake, for my contributions to the designs, I just made small changes to the design Jamie showed me. My changes were in creating the hood shape and the order that I sewed things together. In my case, I think it made the process a bit easier, but Jamie's way of doing it was much more professional. If you are interested in making it, you should get in contact with Jamie about the design. He's been very helpful on a couple of projects of mine. If you are curious about the changes I made, I'm sure Jamie has them and can explain them better than I could, but you can PM me with questions as well.
I've had a chance to use it a couple of nights, and I have found that the bug netting is a little low on my body. Instead of over my eyes and mouth, it is over my mouth and neck. So it still works fine, and I would now agree the amount of mesh is correct. I would also say that the positioning is more because of my sewing than the design. Other than that, I have actually been able to sleep in the bivy without needing any way to pull it off my face like shock cord. It is very comfortable and perfectly roomy for me at 5'10" about 145 (side sleeper) and my Golite Ultra 20. I haven't had a chance to use a thick pad with it, nothing over about .5" because I don't own one, so I'm not sure how it would do then but it seems large enough.