I have an MLD bug bivy and it is very spacious and will easily accommodate a neoair. Some breeze does get through the mesh, but in a Texas summer it is still almost as stifling as a tent. I will often zip the bivy only part way up and then arrange the netting so that my head is sticking out for the fresh air. When it turns a bit colder, I have found that the bug bivy helps keep my quilt arranged around my torso and I just skip the quilt straps. The bivy also blocks some of the wind… perhaps about half but this is much more noticeable in a light breeze than in a heavy blow which is just the reverse of what would be desirable. The bug bivy has two points to hook the netting to the tarp, at the ends of the top entry zipper, but I only use the one at the head. As I am thinking about this I am going to go remove the other.
That said, I am looking for another bivy to use in the colder months. It is not that I don't like the bug bivy, but a lot of times I would just like to skip setting up the tarp so I am looking for a bit more protection from my bivy and a hassle free method of achieving some head room without having to clip netting to the underside of my tarp. Right now, most of my shelter comes from the tarp with my bivy providing bug protection, a ground cloth, and a bit of extra protection from spray and blown dirt. I think I want to reverse that and get a more robust bivy, especially for the colder months, and a minimal tarp that will only be set up when I have a rational expectation of bad weather. Total grams should be similar but the second options will let me enjoy that stars more often and save camp setup and breakdown time especially when the weather is good.
I will be watching this thread for quality products to check out.

