Deco XE70 Pro

I'd go with the TP-Link Deco XE70 Pro, it offers the best balance of performance, future-proofing (Wi-Fi 6E), and value. Great for large homes with lots of devices, and supports multi-gig speeds if your fiber plan is fast. Better value than Orbi 770 unless you really need Wi-Fi 7.

Based on your post I think the TP-Link Deco BE63 would be good for a WiFi 7 upgrade. It has 2.5gb WAN and 2.5gb LAN ports, This should work well with internet speeds up to 2.5gbps. If you have faster internet then this system will throttle (reduce/limit) your speed to 2.5gbps max and you should cons

For a quick, easy and uncomplicated setup TP-Link mesh systems are a good option. You didn't specify your internet speed, so I'll assume 1gbps max. If it's faster than that you'll want to get a mesh system that can match it. For example if you have 2gbps service you'll want a mesh system with 2.5gbp

Or, logically, return the AXE75 and get a Deco XE75 Pro, XE70 Pro, or the BE63 3 piece kit and be done. For slightly more than the single router, you have a true mesh system and can use the wired ports on the units for back-haul between them and/or to connect other devices that you don't want on wir

Look for used ones on eBay or a local marketplace. Deco XE70 or XE75 are pretty cheap.

Deco E4R are fairly old if you want something better and that’s pretty affordable and has newer specifications the Deco XE70 AXE4900 is very good or even the Deco XE75 is also very good both have great range and great speed and would probably do a lot better with wireless speed

Go with a 6E system like an XE75 or XE75pro even the XE70 is very good and priced very well. I would replace all your WiFi 5 units but keep them around in case you need coverage in a certain area your wifi isn’t reaching because all decos will work together but you want the newest model as your main