I completely agree with your assessment of the stability of the Basis tables. And the extra mass in the platters and plinths really makes a huge difference in performance. Even the 2001 I used to own seemed to be very tolerant of what it was sitting on.
I'm finding that I really enjoy fiddling with different tonearms and cartridges almost as much as I enjoy the music, but that could be that this is just the eagerness of the uneducated. May wear off someday. The Vector is great in that in provides, IMO, outstanding performance and it is not really a finicky arm to set up and use. For those who like to "set and forget" it may be the perfect tonearm. At the same time if you are willing to mess with the setup you can be rewarded. I have found that I prefer the Vector with less dampening oil than the Basis instructions indicate. I've filled the bath just enough to contact the entire underside of the pivot. Could be compensating for a short-coming in the 103R.
Like I mentioned before, I'm ready to move up the line cartridge wise. Expecially if I can't get this popping issue remedied. Zyx, Shelter and Benz are on my short list. Alas, the local dealer does not carry these, but I might work out demo of a Clearaudio cartridge. I'm leary of going back because the last time I tried to do business with them it took 6 months to get an IC-70 cable from Graham. Fortunately, Bob Graham took care of this for me very soon after contacting him. Bob is another one of the really great guys in the audio world.
I asked about synergy only because if I decide in the future to go to a 3 arm table then I don't think I could get that in a Basis. I know they have a two arm table. I might be able to get A.J. to modify one, but that would probably not be cost effective. On the other hand, I'd like to try a non-suspended table as well. I realize that this design requires a bit more effort regarding a stand but there are lots of good ideas out there for DIY solutions.