Dynaudio vs Harbeth vs ProAc

@freediver,
I have listened to the Special 40. They are one of the newer models in the Dynaudio lineup. They sound really good, IF front-ended by some very good ancillaries from Moon or Mark Levinson. I have heard them in such a system, wired with Nordost Fry or Vallhala 2. They were playing the Nils Lofgren "Keith Don't Go". So obviously they had to sound good :-)
That said, I took delivery of a pair of ProAc floorstanders today and love them. I have not heard the Response D2, so cannot comment. But based on my experience with multiple Proac loudspeakers, I can imaging they would sound very good. I have even listened to the Harbeths you mention. They are warmer compared to the ProAcs and Dynaudio. Going from cool to warm, here is how I would place them: Dynaudio - ProAc - Harbeth.
Good Luck in your search and I hope you can listen to the speakers in-person.

Value decent imaging and staging with an organic tone that allows you to feel the wood of a cello or violin

You want a Spendor Classic.

I’ll second the proac speakers I always found them very life like. I’ll also toss in another speaker the living voice speakers also from uk very tube friendly and very musical and detailed. 

When I upgraded my system years ago the two best speakers I heard were the Dynaudio Special 25 and ProAc Response SC-1.  I did listen to some larger and more expensive rigs but those were the ones that hit me where I lived.  I haven't yet had the pleasure of hearing Harbeths.

I'm another vote for Proac. I have a pair of the Response 2.5s and there are still very few speakers I would buy to replace my 20 year old pair.  Match them up with some Audio Research gear and you have a match made in heaven.