I realize this is a prototype, so you can't provide weight specs. But how many ounces of fuel are needed to being your 2 cups to boil? And why are you focusing on the Ring of Fire stove design? Does it perform better in low oxygen environments like the open flame cat stove?
You've hit the nail on the head when it comes to oxygen deficiency when incorporating the windscreen into a design that moves heat further up the pot sides, e.g. Caldera Cone. Inevitably I find stove efficiency drops by 1/4-1/2 depending on the stove design. But this drop is offset, to a degree (haha, pun), by maximizing heat output.
I've been playing with increasing the angle of the cone design to provide a larger space for reserve oxygen as gases escape out the top vents. I'm fairly convinced by the concept of the cone, while I work on breakdown designs for packing. Not ready for prime time yet.