In the current RADIUS server, we have to give access to all routers that wants to atuthenticate through it, so if yo add another device, you have to configure the RADIUS server for it. With a RADIUS proxy, all routers will got to it, and only one access (the proxy) will need to be configured in the main RADIUS.
"You're talking about the OpenWRT configuration now?"
No, I was asking what is the integration beetween openwisp-radius and openwisp-controller. If we have configured a RADIUS, when making a WPA2 enterprise template will the data to enter in the RADIUS section be suggested (the configured trought openwisp-radius)? I don't know if openwisp-radius can configure for example the nas-id or secret.