I've been struggling with this issue for several years. I like the warmth, mid-range focus, and musicality of the older gear. However, I have to admit that, stock, it has problems at either end of the frequency spectrum. Flabby bass, muddy highs. The way I was able to find the best compromise, for me, was to alter the sound of the newer gear with NOS tubes, and to have some of the modifiers who know the gear, modify either newer or older gear in a direction that I like. I've worked with Steve Huntley of Great Northern Sound on ARC gear, and Bill Thalman, of Music Technology, on CJ gear. You can either take older gear and update it, or in some instances, newer gear, and tweak it.
In this process, I've become a bit of a gear collector (though I don't keep everything), and am in the process of rebuilding an updated version of my 80's system (CJ/ARC gear with Dahlquist DQ10's) in addition to my main system.
Here are some things I've tried, and my reactions:
ARC LS15 pre-amp, modified by Huntley, with Bugle Boys - quite nice, but sold in favor of:
ARC SP8 pre-amp, modified by Huntley - I like it, but haven't worked out the tubes. It will go in the new/old system.
ARC VT 50 and VT100 mk iii amps - In the end, I don't like the Russian super tube. The VT100 in the 4 ohm tap was pretty nice, but in the 8 ohm tap was too bright for my taste. (I can't recall what was in the VT50, but it was a bit underpowered for my needs.)
CJ Prem 11 amp, modified by Thalman - my main amp at the moment. Very nice "in-between" sound. Warm, good control in the bass, detailed and very clean top, but not in-your-face.
CJ MV 75a amp, modified by Thalman - sounds like exactly what it is, an MV75 with 80's sound, but with very clean top and bottom. Very musical.
CJ PV5 pre-amp, modified by Thalman - very nice, but not quite broken in, and I think I prefer:
CJ Prem 14 pre-amp, stock, but with Mullard tubes - I've read that this is the last of the "classic" CJ-sound pre-amps. To my ear, it is another fine in-between sounding unit. I intend to have Thalman tweak it, but it's pretty nice right out of the box, with the Mullards. This is the pre-amp I'm using now.
Cary slp98 pre-amp, various tubes - This is supposed to have something of the "good old tube sound." I didn't care for it. Many other people love it. Maybe I couldn't find the right tubes for it. But mine had silver wire in it, and it sounded like it had silver wire in it, and I don't care for that sound.
Cary slp 2002 pre-amp, stock - I preferred this to the 98 (again, in contrast to others' views). To me, it seemed like a good "in-between" pre-amp-- somewhat lush, but with pretty good extension and bass. And you can roll tubes.
VTL ST150 amp, stock - This is a good example of a solid, basically clean sounding piece of gear (especially in triode mode) that is just a little too "neutral" for my taste. The mids are not particularly warm, although preferable to solid state. The highs were slightly "hot" for my taste, though very clean in triode mode. I might have liked it more if I'd rolled tubes, or if I'd updated it. (It was a 2002 model.)
BAT VK31 pre-amp with bugle boy 6922's - I like the non-SE versions of the BAT gear, b/c you can roll tubes. The VK31 is a good tube-rolling platform. I was using this before I started with the CJ gear, and find the CJ gear a bit warmer, but this is a nice piece.
BAT VK75 amp with NOS driver tubes - Good mate for the VK31, for the same reasons. I tried the version with the 6H30 "super tubes," which I found impressive, but, for my taste, too emphatic on the top end detail. This also I was using prior to the CJ gear. Nice piece, but I lean toward the somewhat warmer CJ sound.
Joule LA150 (I think) pre-amp - This is a nice piece of gear, on the warm side, but very revealing in the highs. In the end, the synergy wasn't there, but I can see why people like this pre-amp.
That's been my journey, and, at this moment, I'm basically leaning toward 90's or modified (or both) CJ gear to get the good old tube sound, with reasonable extension in the top, and reasonable control in the bass. But other pieces mentioned above have very nice characteristics that will appeal to others. It's really a question of what you're trying to get out of your source material. I used to like the "wow" factor...musicians in the same room with you, etc., etc. And my system went too far in that direction, meaning it was very, very revealing. The problem with that is that, after a while, you realize that you're not listening to a whole lot of things, because they don't sound good on the system. They weren't recorded, mixed or mastered with extremely revealing systems in mind. (That's a very simple concept that took me years to understand and accept--if a particular recording was mastered using wildly different equipment than that on which I'm trying to play it back, IT VERY POSSIBLY WON'T SOUND LIKE THE ARTISTS WANTED IT TO. And that's MY problem, NOT theirs!)
Then one day I realized that I just didn't like hearing much of anything on my system anymore, and the Great Gear Search began (first as a speaker search, then electronics). That also led me back to vinyl. (I'm still amazed at how many "problems" got solved when I went back to vinyl.)
But, this is enough. Thanks for bringing this up, Mr. Tennis.