I use a wifi router in bridge mode to provide the wifi capabilities using the stock firmware, and a NUC like device running Ubuntu with two ethernet interfaces

I use a wifi router in bridge mode to provide the wifi capabilities using the stock firmware, and a NUC like device running Ubuntu with two ethernet interfaces to do everything else - NAT, DHCP, LAN DNS, firewall, etc... I've thought about trying to do everything in the NUC, but at some point, just configuring it all is sorta a pain.