"now I am looking for problems/issues that I didn't know existed." I am not sure you found a problem, but rather just a simple fact. In my experience, line conditioners are best at elimination RF interference. If you hear a radio station when playing CDs or LPs, your system needs help.
I run #8 wire to 30 amp dedicated outlets for each amp (2) and separate 20 amp circuits for source components (one for all) and accessories (100 total amps available for the system). The reason is not to reduce noise, but rather to improve the amps performance by limiting voltage drop. Amps cannot deliver their rated power at spec when not receiving their required voltage. So your dilemma may become one of thinking the system is less noisy after installing the dedicated circuits and bigger wire, when in fact it may be due to improved amplifier performance caused by a change in the delivered voltage.
What is the rated amperage draw of your amp(s) at rated power? I doubled mine to determine the size of the circuit I used, to allow for peaks. I doubt I reduced the a/c line noise and the system did sound better to me after the change.
I guess this makes me an Audiophile, or at minimum obsessive.
