Configuration Help - Local LAN - Changing WiFi to Internet

My environment is fairly unique. I travel in an RV. In the RV I have a LAN (192.168.1.X) for file sharing, printers, TVs, Roku, etc. I have a TP-Link CPE210 set up as "AP Client Router". The CPE210 (Access Point) pulls in WiFi from either a campground or a Verizon or AT&T MiFi hotspot. The CPE-210 is a high gain, directional WiFi device. It then connects to the wired WAN port on a standard ASUS RT-N66U, which provides the local LAN (both wired and WiFi).

Other than possibly being blocked by certain campgrounds double NAT is not an issue, IE I don't "host" anything. I simply need browser/connectivity to the Internet.

Using your documentation notation I believe this equals:
clients ↔ Local LAN (NAT/DHCP) ASUS ↔ OpenWrt Router/Gateway? ↔ ISP router with NAT ↔ Internet

This works well and seems to be optimum for the native TP-Link but I bought a second CPE-210 which his now running OpenWrt which adds significantly greater capabilities.

Keeping in mind that periodically (few days to a couple weeks) I need to access a new WiFi hotspot...

Is this the right configuration for OpenWrt? Any thoughts are appreciated.

Is there a better way? In reading the documentation it sounds like I can bypass the whole WAN section of the ASUS Router and connect directly into one of it's LAN ports. Then the CPE-210 and OpenWrt would be the access point and the Router/Gatway. It would provide DHCP and NAT to the local 192.168.1.X network.

Sorry for the complexity of this question. I appreciate any assistance.