The range extender were kinda useless for me. It is not stable and drops signals. My house wasn't big (for extender to be useful), the issue is walls. Sounds like if I were to use devices on extender ID, I will experience slowness due to sending back/forth which makes sense. Maybe I should remove the extender altogether. The extender is hooked on to the 5GHz band.
I don't quite understand what you mean "set 5GHz for communication to the router and 2.4GHz for clients."
The owner of the car lot bought the building next door. He moved staff in but there was no Internet. I bought a single band (radio), 2.4 GHz range extender, installed it and we had connectivity to the main building. There was a sizable hit in performance (like everyone said there would be) but it didn't matter because it was still faster than our slow DSL Internet connection.
2 or 3 years later it died and I replaced it with a two band (radio) range extender and configured it as I had mentioned; one radio dedicated to the router and the other to client devices. In theory you can set up any dual band extender this way
if the user interface gives you the hooks to do so (and I couldn't tell from your screen shot if you can).
I had picked a Netgear 6150 (going from memory) that bragged about "fastpath". With the click of a couple of buttons I could dedicate one radio to the router and the 2nd radio to all the client devices in the 2nd building. (With a single band/radio the radio
shuts down to the clients while it talks to the router. Kind of like those old walkie talkies we used as kids. where when you pressed
talk to talk no one could talk to you.)
Worked great! Local speed tests showed virtually no performance hit, in fact it even ran better than some of the clients in the main building. Users even reported that the
"lag" in interactive browser sessions was gone.
Since you have the range extender you have a
toy to play with it you like. Move it closer to the router, not too close but closer, and see what happens. (BTW channel 9 on your range extender is kinda too close to the channels (7 & 8) you're using for your router. Who's using all the channels? Neighbors?
If they're far enough away / their signal is weak enough you might be able to get away with one of those.)
But, yeah, you convinced me. See what happens with your new router. Keep the range extender in case you have a dead spot in a far corner of the house.
Best of luck!