That upgrade will become a nightmare, so when it does - remember this.
Turn in the Technicolor CGM4141 back to Cox (get the free phone eMTA) and buy an Arris/Surfboard SBG8300 DOCSIS 3.1 Dual Band. You'll have two guest radios (or disable them), parental controls over ANY online device and more.
If you want to extend the internet signal to every room you have a coax jack, then get an ECB6200 MoCA adapter and a few WCB6200Q network extenders. They will create full speed ethernet connections and 2.4 GHz/5 GHz radios anywhere you want them...