Well, whaddya know, first attempt in the power domain was a step in the right direction. Thanks for the inspiration, @audphile1 !.
I'm always open to tweaks, and one of the more recent which I forgot about was the addition of Vera-Fi Audio's MainStream & Snubway line and noise conditioners. I had the latter previously, it didn't add much, returned it. The MainStream came out and there was a promotional package for the two, as they work in tandem. People extolled their virtues and I thought, why not give it a whirl again, to see if anything changed? Vera-Fi has a good return policy, so no harm, no foul.
The MainStream should be plugged into the same line as the system. This morning I pulled it out of the receptacle that feeds my system and the result was subtle but noticeable: less glare, less edge. I'm not saying the MainStream or Snubway are not helpful, but in my system, to my ears, it appears it might have been too much of a good thing, revealing so much as to add too much clarity. They could be just what your system needs, but I am better off with it on the sidelines, at least for now. After a few days I will plug MainStream back in, to see if the difference was perceived (wishful thinking) or real.
The power cord trick is next.