Lcherepkai, No, I really don't take issue with cables as tone controls to "sculpt" the sound. I personally find them quite necessary to bring out the best in a system and look at them as a means to do a little fine tuning. That is, after putting together components and speakers that already work reasonably well together no matter what cables are used.
Some components and/or speakers may never sound good, no matter what cable you throw at them. Changing a wall outlet or the end of a power cord strikes me as something akin to grabbing at straws.
Sorry to offend but after reading your trials and tribulations with power cords, plugs and wall sockets, hoping to tame aggressive sound, I can't help but think you're spending your money, and lot's of it, on the wrong things.
Regards