I've finally found the time to install and setup OpenWRT
19.07.5 r11257-5090152ae3 on my R7800, after a long time of purchasing it!
I think I've got the setup working fine, setup PPPoE, got internet going fine, setup WiFi without a hitch, and DHCP Option 6 to setup a PiHole as the primary DNS resolver, and dnscrypt-proxy2. Everything is going perfect.
Thank you for the detailed documentation, and sane out of the box defaults. Had everything setup in under 2 hours. I'm really happy with the setup!