I am familiar with OpenWrt operating system for wireless routers.

I can work on VPNs (OpenVPN and WireGuard), DNS over HTTPS, DNS over TLS, separate network for each Wi-Fi SSID, guest network with password being reset periodically, router to reachable globally and more.

I can configure a router via another device which I can control remotely, e.g., with an VNC, and which can be connected to the router.

I can also give suggestions based on your ideas.