Yes, another audiophile at a crossroads story and request for advice

I am going to throw this out there, it seems like your system is solid for what you are using it for. Have you thought about replacing your current speakers and opting for a NOS set of tubes in your Integrated and dac? I have been back and forth with SET systems and regular push/pull tube systems and I loved the texture I was getting with my Klipsch Forte IV’s with my 45,2a3 & 300b amps but I ended up missing that extra headroom from higher powered amplifiers. I used a Audiomat 30w integrated with my Forte IV’s and loved the extra oomph and used that as a place keeper until my what I call my Super Quad ESL 57’s were being created by Kent at Electrostatic Solutions in KC(Robin Wyatt YouTube video for reference). I only mention the Quads as my other pair of ESL 57’s sound exceptional with the Audiomat EL34 tube amp. I used my Audiomat with Holland metal based EL34’s and 62’ Mullard 12ax7’s and it was everything you are looking for in sound. I am done with my search with the exception of a DAC as I miss my Wavelength Cosecant N2 dac.

My current setup:

Herron Audio 360 ESP Reference

McIntosh MC75 original issue with GEC KT88 NOS and Telefunken driver tubes.

432EVO Aeon Streamer/Roon Core

Rockna Wavelight Dac

Herron VTSP-2a phono preamp

STS Thorens TD-124 with Jelco 850L and Ortofon TA-110 Tonearms

Koestsu Urishi Black and Haniwa HCTR-01 Mki MC cartridges

Solid tech rack and Still Points ESS rack

cables are Western Electric speaker wire and Herron Audio Interconnects

Good Luck!!!

@wolf_garcia I’ve read good reviews and your positive comments regarding use of the Loki to sculpt the sound to taste is an interesting idea. My RME DAC has a graphic equalizer feature that I’ve not yet used or explored. I’ve been reticent to try it, but I should check it out before changing out any hardware. 
@zlone I got into jazz about 15 years ago, all my records were bought ~ 10 to 15 years before that so all my jazz physical media is on CD. If my no cost experiment of engaging the equalizer in my DAC doesn’t provide the sound i’m searching for then I’ll try a higher quality SPDIF cable. Do you have one you would recommend for my current system and sound goals?

@ezstreams that's the hard part to suggest, I think, since there are so many possible combinations of gear, tubes, peoples listening perceptions, etc.  

For me, I just kept a notebook and marked down how each combination sounded so I could refer back to it.  This is especially handy when swapping out speakers to help get the right combination.

You could just try ordering some different sets to see what works.  Another thing I ran into was that just because a tube is more expensive, doesn't make it a better performer in a given application.  Sometimes, a cheap tube can sound great, just as an expensive tube.

A DAC with a graphic EQ? Who knew? The Loki Max is a deluxe EQ unlike anything else out there (in the analog world anyway). 

Do you have one you would recommend for my current system and sound goals?

I am deeply ashamed (not really) admit that the best one I have heard to date was a Neardost from AliExpress. I had used two or three other cables before that, but when I put this one in the mix, the clouds parted and the sun shined. I understand if you don't want to go that route, but if so I can give you specifics. Alternatively I was recently given a recommendation to try the Acoustic Zen MC2, there are some good deals on the used market for this cable. 

I got into jazz about 15 years ago, all my records were bought ~ 10 to 15 years before that so all my jazz physical media is on CD. 

I started listening to jazz seriously about five years ago and have been improving my system to get more of the same instrumental information that you are seeking, and have been fairly successful. Maybe try something acoustic on vinyl to see if it has more of the feel you are looking for. Sorry to belabor the point, but your situation is somewhat confounding given the quality of your equipment. It reminds me of the sound of my early, jitter-rich digital system compared to where it is now. So, trying to eliminate the digital entirely and see if you hear more of the instrumental details you are looking for in the analog world, which would narrow the focus of where the problems live.