Bingo!
You state:
”The sound is good but rather lightweight, neutral and nimble but polite, one might say meek with tight but lean bass. ” Exactly what I heard the times that I heard the original CLS.
For whatever it may be worth, from the Stereophile mag review of the CLS:
-“The bass was a little lightweight, there being a lack of upper bass”.
-“there was then a hole before the relatively sparse low bass came in.”
-“the bass being definitely a little sluggish compared with the treble”,
-“Another aspect of the CLS sound bothered me more in the long term: a lack of dynamic range in the lower mids and upper bass”.
If you are planning on keeping the CLS (it does have a beautiful transparency), my suggestion is to look for a VPI SDS motor controller. Bass will be improved to a degree that no mat, clamp or VTA adjustment will approach, and most importantly dynamics will be greatly improved. Music will be less polite with much more sense of groove.
Good luck.