That’s great that you could get the chair under 10 oz, especially with strong parts and materials. The foldability to an easily carried tube shape is super.
It might add some comfort and ventilation under the seat by adding 4 short pegs, one at each corner. The rear ones would be extensions of the back rest supports, but the slightly longer front ones would need a way to hold the front pegs steady. A number of ways come to mind: for example, a flexed bent rod or narrow tube at the front might do it.
Regardless of the seat and back, many of the chairs use fabric. There are many types of strong meshes that not only provide ventilation, but keep rain water from collecting, not just behind the back, but also under the butt, which can be hard on the nethers underneath. The challenge is to find a mesh material that is almost as strong as the ultra light fabrics, but also light in weight. A drenched back and seat can become something awful. But using a tent with an awning that protects against downpours helps a lot, especially if much of the chair back and seat can be slid back into the tent.
The above approaches may be a little heavier, but allow me to cook and have dinner out of the rain, especially if it is an intense downpour.
Hope some this is helpful. My chair is somewhat heavier, but very sturdy and stable when sitting on it, especially in heavy rain and/or wind. And it also fits into a canoe, solid or inflatable. Then a WPB fabric designed to fit over the canoe rails and cinched around the waist and WPB parka and hat keep me dry when out there on the blowing rain, wind and lake water.
