I would add to your impressive list the TAD CR1's (and not just because I sell them).
They present a tremendous amount of detail woven throughout the spectrum, yet are not bright, brittle, fatiguing, thin or mechanical sounding.
Either tube or solid state can yield very natural results. I get to hear live acoustic instruments from up close on a regular basis and the CST beryllium driver delivers many of those qualities I hear live.
Another thing it excels at is taking average or lesser recordings and revealing so much information that they will sound like an audiophile recording. I've heard pedestrian recordings on outstanding cutting edge systems (that are great with stellar recordings), just kind of lay there. Back at my system those average recordings come to life with inner detail, vitality, complexity, drama and naturalness.
Best of luck in your search for a reference speaker.
