Just made the switch from coax to ethernet on the ONT to enable increased speeds. With that, the G1100 router moved to the basement because I have zero ethernet jacks in the house. I've had good success with the WCB6200Q network extender, but with the router moving, wifi on one end of the house is noticeably weaker.
I can get another WCB6200Q on eBay and take care of the other side of the house. Or, is there an advantage to putting in an eero or Google Nest mesh network? I can use moca adapters if wired backhaul is a big deal.
Right now, we're at 100Mbps but likely to upgrade . . . probably to 400 at first.
My personal preference is with wired backhaul. Wireless backhaul is a case of garbage in, garbage out, and you'll come across consistency issues in time. At speeds of 400Mbps or up you might also find the satellite nodes having trouble reaching those speeds. Wireless backhaul without a dedicated backhaul, you'd also run into an issue with every node running on the same channel, which is not good.