Yes, that makes sense!
How do I prevent "interference" of signals on the same frequencies from overlapping ?
Are there "smart" routers that will talk to other routers and operate on different frequencies to prevent cross signal saturation ?
The reason is that I am currently using hodge podge mix of different routers all on wired LAN using same SSID & key:
- ISP supplied 5Ghz AC band +
- Apple Time Capsule 5Ghz AC band +
- TP Link AX band
The signals all interfere with each other depending on where the user is located. Sometimes the far away weak AX router will not let go and switch to a closer AC router.
I just set them on automatic for the radio and have never had an issue in my house or places of set a similar setup up.
However, devices won't jump on WiFi like you are expecting. It doesn't work like cell towers. My understanding handoff or roaming on WiFi is totally up to the client device. The network doesn't say jump to this AP. The device decides to. Because while you see the SSID 4sallypat when selecting your WiFi. Your device sees all of the access points using that SSID and selects the best. There's utilities which let you see them as separate entities, at least on Windows.
Unfortunately devices don't decide to do handoff very often. They'll dig in and stay on the same AP no matter how bad the signal is and won't switch until it can't see it anymore. This means you need to cycle the WiFi on/off on your phone or other device. Then it'll connect to the best signal again with the highest SSID priority (presumably your network is the highest not a neighbors). My understanding the issue is the same with Mesh.
This also means if you get something like a Ring camera. Mount it where you plan to use then connect it to your WiFi since they don't have a restart button. Otherwise you'll be dancing a router power cycle ballet to get those cameras connected to the right AP.
You also wan't to make sure the encryption type is exactly the same. If one is WPA2 and another is WPA/WPA2. It'll cause all sorts of issues. It needs to all be something like WPA2 AES.
On 2.4 you could manually set one to the lowest radio channel, one to the middle and one to the upper. 5.8Ghz has more options and really should be automatic. I also only allow AC devices on 5.8. Everything else is old and I pigeon hole them to 2.4. You could also give your 5.8 a different name so you are sure AC devices only try to connect to 5.8.
Do you have DHCP disabled on those meant to be used as access points? You don't want conflicts between multiple routers running DHCP or Double NAT. Those access point routers should be have their MAC Address reserved in your main router. So, you can find them with their web clients by IP address. Then the Ethernet plugged into their LAN port not WAN. Unless it supports bridged wifi/access point mode. Which the Time Capsule does.
At any rate. It sounds like you already have a good hardware setup. Assuming your house isn't huge or especially bad for interference. You should have a very good connection already anywhere in your house. You may just need to tweak the settings some to make sure they're all optimal. Plus remember that a roaming device like a phone probably needs the WiFi cycled when you move about the house.