Wouldn't good amp stands fix some or all of the issues being talked about here?
Aside from air borne vibrations, or issues concerning non solid flooring. Why not set them back several feet from the front plane of the speakers?
Have those with monos being placed in close relationship to speakers actually seen substantial diffs from the use of six feet or less of wire to say eight or ten, or even four?
I've noticed only a minor amount of diff in the use of a five foot cable vs. a six foot. Very minor in fact. Whitout having them side by side to compare, one would never know.
I'm considering placing my monos out into the listening room too. Though, I doubt I'll do it as it congests the esthetic, and adds clutter... thus far I'm OK with running longer speaker cables to avoid that issue.
But if it's a night and day diff? Well.... maybe.