HI Dave,
I want to have a beer with you…
You are correct in every point, no question!
I think Neil has enough information to make a really good decision.
I always value you point of view… always looking for the “exception” Super valuable!
All the best!
Ty Dave Timot Eschwenk Aisle 6 Shadow and Almabes, All your assistance is much appreciated and I will invest as advised. You have all been smashing- A privilege to be on here learning. Thanks to everyone. Neil.
Absolutely no problem.
Dave
It should be stated also that in most cases and with short cables you might not notice any audible problem when using a “unbalanced” Adapter when connecting a balanced output.
It depends a little bit on the exact position of the jack contacts (with some cheap “made far away” jacks they short-circuit the wrong contacts and then you won’t get any signal at all).
In most cases you will basically turn your balanced signal into an unblanced one. Of course, that is not your intention but i doubt that you have an even audible difference with short cables and line levels. And you won’t damage anything.
So don’t wonder if the “wrong” adapter works as good as the “right” one. That is kind of “by design” 
A good way to basically avoid ground loops is to us e a single AC Phase, a “star” AC Wiring topology and as short ac cables as possible. Of course, this will only work as long as your equipment does not drain too much power.
So if in doubt about the stage electrics, ask for a CEKON Socket, plug your own “Cube” into that and wire your equipment from there (maybe one dedicated phase for instruments, one for light and the third one for things like Notebook/Beamer, Fog Machine, score pult lights, beer fridge or whatever else you need to have on stage).
That may bring much less stress than getting a shared “Schuko” Line which maybe also used by Coffee Machines and Waffle Irons so you never know how much current can really be drained from there.