What's the next upgrade step??

I I second the TWL mod:

http://forum.audiogon.com/cgi-bin/fr.pl?eanlg&1032024188&openfrom&2&4#2

You're system is pretty well balanced. Are you looking to replace the whole thing? If so, what's your budget? If you're willing to go for it, I would suggest moving up in the Basis line to the 2000 and going with their Vector arm and pairing it with one of the Transfiguration carts but that will run you over $8000 list. You could do it in steps in just about any order with good results. In your case I would prioritize the arm, then cart, then table.

On another tack, you could try TWL's lead outrigger weight tweek for almost nothing - effective, reversable and fun.

dealer disclosure.

You can experiment with different brands of tubes. Also resistance loadings
if your unit allows.

For more midrange lushness you might want to look at other cartridges than Clearaudio. Maybe a Shelter 501 or Benz cartridge.

Shakey

I have changed things more than a couple of times and always found that once I have a good arm, cartridge upgrades provide more bang for the buck. Moving from one top grade arm to another may change color, etc, but I could live with a Phantom, SME, VPI, Triplanar, etc.

What does your table sit on? A deadicated stand, sand or shot fillable may be what you are looking for in your present system.
Good Luck

Leave well enough alone and get more LP's and a RCM if you don't already have one.