"Sorting out the digital front end: switches, cables, filters, servers, power supplies, power cables, isolators, USB tweaks, EMI shielding, software…. the better part of 5 years and still only 95% there?"
I get it antigrunge2 except don't be thinking 5 years is a long time.
I've been doing all that for 30 years. It would be a long post to document it, revealing absolute insanity and musical satisfaction. For me, as improvements were made, the opportunity to improve further by maximizing the performance of the major components has been a continuous quest. Major components then sneak in and the process repeats. I may have learned quite a bit but the most important is that: EVERYTHING MATTERS
I'm done with it now and just enjoy the music. (Did you actually believe that??)