Another dedicated line question

It appears that ideally, one wants a dedicated line (DL) for digital, one for analog, and one for and each and every power-hungry device. I would if I could, but I cannot. I live in Chicago and have to use EMT/conduit. Running an interior DL to my listening room was difficult so I went outside, piggybacking on a run to a newly installed mini-split, placing a box and then drilling into the living room wall as the conduit passed by. I had the electrician pull two additional 12ga hot/neutral wires for a total of six 12ga wires in half-inch EMT.  Each of the two new pairs has its own 20 amp circuit breaker. 

I’ve done a lot of reading since the installation and have some questions about how to most effectively utilize this access.

System includes a Devialet 400 (800 watts) driving Wilson Benesch Vectors, (89db/m/2.83v), Dayton SA1000 (1000 watts) driving a DEBRA Swarm,  a VPI HW19 Mk IV (with SOTA Condor and Roadrunner) and Sonos streamer (soon to be significantly upgraded). I include this info to give a sense of my power requirements. I presume the DEBRA subs relieve the Devialet of some of the heavy lifting, so I doubt I need anywhere close to 1800 watts for any prolonged period of time. 

I can use each of the new pairs to give me two 20 amp circuits, but some folks are concerned about running multiple DLs in the same conduit because of the impact on the sound/interference/noise, etc. Somebody has gone so far as to say that a true DL is not defined by a unique circuit breaker but rather a unique path. I recognize that the mini-split poses a similar problem, but I can turn it off at the breaker or install a switch when I listen seriously. 

I then read about a concern with Isolated grounds and metal boxes/conduit and how that impacts on the sound/interference/noise etc. So alternatively, I could use one of the wires of the second pair to serve as the connection for an isolated ground. 

Bottom line, which is better? One line with an isolated ground or with twice the power but in a shared space? I recognize I have enough room to pull two additional isolated ground wires but again, the issue of multiple wires running randomly alongside each other is a concern for some. 

Also, where might a power conditioner fit into this? I see some that run a relatively unprocessed signal to high power outlets and then provide filtered current to others.  Could this serve to isolate my digital from my analog or can one accomplish this only by DLs? I already have an EP-2050 on the main panel.

In anticipation of the “try it both ways and see which way is better” replies, I currently have it hooked up as a single line with isolated ground. I’m getting used to the sound but it is limited since my wife works from home. I anticipate I will have many more opportunities once this Covid thing is over, but I would rather not change it if the consensus is that this is the superior way to do things. If there is no consensus, I will try the other.