I have experimented with a few different DACs and settled on the Chord DACs. Totally hear you on the R2R idea, problem is when I have tried some like that- I've found them slow, or noisy or I don't like them. I don't think these were high level- Unison Schiit Gungnir I think was the highest level. I preferred the Chord Mojo 2 believe it or not, even though the layering was better on the Gungnir. Also regular DS dacs like Mytek Brooklyn I've found absolutely awful to my ears. It's the upper midrange, 4k area. The Chord DACs seem to give me most of what I want and none of what I don't. I think part of what also is an issue with the VC is that it's closed and with tinnitus I think this adds pressure to the ear drums and increases ringing in the ears. I might have to accept that closed is not the way to go.You absolutely have the right amp. I've heard a VC with my V281 (2-3 yrs ago, so grain of salt, etc), and it is a bit bright. Or maybe just so dynamic that the upper mids hit harder...? Never too sure about the tone vs dynamics seesaw.
You don't have a comprehensive profile, so I can't be sure of certain things, especially cables. But I would use the best copper-only headphone cable with the VC.
And at the risk of suggesting more "change something else" steps, you might want to investigate a multibit or (better yet) NOS DAC. I suggest that not because it's some kind of tone control for the VC (not that at all), but because DACs of that type often sound more natural, flowing, and musically realistic, with no frequencies spotlighted, as can happen w/delta-sigma designs.
No absolutes here, of course; implementation is all. Still, my experience was that I started getting somewhere overall in both my desktop systems once I bagged d-s DACs.
I have a very irritating preference in that I want maximum attack, slam and dynamics but, that is often a problem for tinnitus. So it's a bit of a game of whack a mole trying to find what fits.
Definitely a great recommendation on a high quality headphone cable, that's next on the list I think, but they do cost silly money these days.
All existing interconnects are copper or non-brightening types.
The timbre of the VC is astounding as is the resolution. For slower paced music, they are incredibly good. For faster harder stuff it can get a bit much for my ears.
Definitely worth tweaking a few things first though because it's very good.