The concept of this chair is to optimize the costs of production, make it easy the transport and delivery and allow the customer to easily personilize and mount the product. I have reach these goals with a design that can be easily done in different materials from wood to plastics and also glass or metal but i suggest the wood. (walnut, oak and rubber tree as you said are optimal materials). The chair can be mounted all with joints without the use of glue, nails or screws. The pillows are attacched at the sitting and the back with simple metal snap buttons in order to permit an easy cleaning and a personalization of the colours (this construction element isn't represented in the project). You can try to produce with the CNC machine the entire piece of the back and the sitting or eventually fix the trapezoidal joint to them with screws but you need some tests to see what works better. The chair can be personilized using different materials for each structural part (see the example in the renders). The fact that this chair is made with only 8 pieces allows the customer to easily transport it and eventually change only damaged pieces.
The name "Zǔ 组" comes from a convivial use of this chair that is thinked for home and family but at the same time can be also used for conventions or business activities. Hope you like my idea and i would be really happy to see it accomplished. Cheers
P.S. I have seen that there is a limit of 4 render but i need to upload more in order to show the joints so i will upload big images to be cut in 4 by your technicians, hope it is good for you
P.P.S. Here is a link of an animated gif image of the chair: https://giphy.com/gifs/chair-z-3og0IHsWDIAzMrfoaY/fullscreen