@skywatch This could be a nice idea. But I never experienced this kind of setup.
Can you assign node id for NRF24l01+ which is attached with RPI? AFAIK, it should be a gateway node right? If yes, we should not have more than one gateway node in a network.
My other easy solution, Keep RPI with a private wifi router, hide ssid and do not connect to the internet. In this case, you can have a controller in one place and from another place you can access the controller via your private router.