Hardware for building a router (experiment)

Hi there. This is entirely for research and learning purposes, not really for commerce.
I had been studing the structures of the mayority of AP's, and really they consist of some CPU and some radio chipsets on the PCI bus.
My idea, maybe crazy, is to take a compute module 4, and from the gigabit port get the enthernet uplink, and by the GPIO manage leds, debug and all that stuff, and from the PCI lane, send it to a PCI switch, and from it connect 3 radio pci chipsets and maybe a switch hub, or connect 4 radio chipsets, and controll them from the compute module 4 with open wrt, and since is open source, modify interface and operations and maybe even creating a new whole access point. The thing is, while doing some research, using for example intel AX200/210 isn't a good idea even if it is so popular, and getting other chipsets like from broadcomm is too expensive or is a dead end, so anyone can suggest me what chipset to use, which for testing would be reliable to use? My plan is to buy the wifi chipsets and the compute module 4, and the main board desing it and print it. Or anyone has any better idea of how can I make my own access point from scratch? The main idea is to build it from "0", not to use an existing one. Any idea is welcome

"we" use a reasonable price product of router as a development board, not conversely.