Thanks to all for the response - hopefully i'm not contradicting myself with each post I make - i'm still mentally iterating through my design, and what would work best for me.
I just got a ZPR68 for the zoned audio, and am using CQC to control it all. I'm trying to determine the appropriate h/w that I should use to interact with CQC for audio in the kitchen.
If it were just the phone, a specific solution like mute-on-call would work. There's an open-ended # of times she'd want to quickly turn down volume [i.e., no off-hook loop detector for screaming 2yr old]. My issue with the tiny little redrad single-gang LCD displays is that while they may work fine for lights on/off, audio up/down/mute, they won't work for audio selection. I'd need an alternate solution for that, and I don't want 2 LCD wallmount displays.
I wish RedRadio UTMA would have 7" monitors; those 10" and 12" are gigantic, far too big for our kitchen. That might be a happy medium, where I can design a UI with big huge mute buttons that are easy to lunge at and press when it's needed quickly.