Wired backbone always better than wireless. Less devices on the radio. Less collisions. Less interference. Wire everything you can. Everything that is more or less stationary.
If you were to pull a wire you’d have more devices on a wire and less devices on the radio. Better for everyone.
If you were to go for “wireless mesh system” and add even just one node you’d have all the devices that you have now +1 node on the radio AND ALSO +1 channel consumed to talk between the nodes wirelessly. Maybe ok, maybe not. You’d need to assess your radio environment to make this decision.
Latency is somewhat orthogonal topic. If you’re into latency-sensitive gaming you’d want a “gaming router” that could prioritise traffic from a specific client/port on the device. You’d also want a QoS/shaping/queueing set up to fight the bufferbloat.
Most modern “gaming routers” are expensive devices that would also allow you to add more nodes at a later point. Wired or wireless.
This type of data needs to be collected at the point all the traffic flows through.
I.e. your router/gateway.