It appears that the Ufer can be placed elsewhere, not baked into the footer and that is not protected by a vapor barrier when building new. Some dedicated horizontal trench placed near the house perimeter as an example (like @wil is doing with the Bentonite Clay but in this case using the concrete of the Ufer) without a vapor barrier so it can absorb as much moisture as it needs.A Ufer is NEC required and they will install one if your building new. If your adding onto the house and they pour foundation, be sure to ask for one to be added.
Vapor barrier is an absolute NO. I completely defeats the ground. Thats like saying you want to wrap your ground rods in an insulated jacket before burying them.
Audio performance may be very important but I'm not one who would put it above protecting your foundation from moisture intrusion. I've lived in and seen many houses that fell victim to this kind of thing over a long time and its not pretty.
But with that said, in the area I live now, using one is probably less important as it was when I lived on the East Coast. We got 10" of rain in an afternoon back there, or at least it sure seemed that way at times : )
I'm not here to disagree with the importance of proper distribution/breaker panel wiring and layout. I have no doubts that it can make or break the ultimate potential of an audio system.
I believe I have experienced and lived with a triple threat in the past where I had a crappy grounding scheme in the 120+yr old house I lived in, crappy breaker panel wiring/layout, Knob and Tube and an expensive set of amplifiers (Paperweights really) unable to cope with any of those things or the load of the speakers they were connected to. Its not a fun situation to be in and was very expensive to try and get out from under.
The funny thing is, once the well designed Pass Labs Amps I own now were placed in the above situation they worked without blinking. So yes, I agree, proper audio equipment design also plays a big role in how everything turns out when its placed in a less than ideal environment and all connected together.