I'm admittedly not much of a networking expert, but you might be able to improve your existing network by running Ethernet backhaul for your mesh network (assuming your access points support it).

Regarding whether you would benefit from a router like that: I've only got a 25Mbps connection, so my main use case for it is using ZeroTier to access various services on my local network, more advanced firewall controls, and the dual 2.5G Ethernet ports for connection between my main PC and home server.