Is table really more importsnt than cartridge?

Both of your examples are extreme mismatch. Playing a $2000 cart on a $200 table will not be acceptable. A $2000 cart will most likely be a mc or a high-end mm, they will require a precision arm and careful setup to sound good. A $200 table just doesn’t have the precision they need. It is a waste of cart and money.

Playing a $200 cart on a $2000 table is a more acceptable mismatch although I wouldn't do that either. If I had $2200 to spend, I would have bought a $1500 table and arm with a $700 cart.

In your case, the Shure actually is a very good cart (I have one) and it certainly desires a better table and arm to show its stuff. But for $450, I doubt you can buy anything significantly better than the Thorens you already have. If I were you, I wouldn’t do anything right now but save more money toward a better table and arm, probably a used set in the range of $700 to $900.

No matter how complexed could be the decision point there's always a limit or the point after you won't recognize any improvements no matter how big and expencive your analogue setup is. In addition to the two mentioned variables here comes certainly a phonostage that could be palls with $300 cartridge and give a complete mess with $1000 one.
I guess that $2000 for the cartridge is just as far as cartridges can go no matter how big and expencive your table is and contrary $200 isn't enough even for cheap DJ one. The same I could tell about turntables that retail above $4000.

Thanks for the further thoughtful and helpful responses.

Newbee: Actually, I'm not sure what I'm looking for, since, for me, the present rig is as good an analog system as I've ever had. But as I read about equipment it seems clear that there's probably greater musical depth, detail, dynamism to be extracted from my lps than I'm getting now. Again, since I just got back into analog about a year ago, after 15 years away, and since I now own a better rig than I had back then, I'm curious to see how much more rewarding the vinyl experience can still be. Couple that curiosity with the new idea (to me) that the table itself is an important variable in sound reproduction and I began to wonder whether my table or my cartridge might be subject to greater improvement. My intuition, which the majority of the posters here and elsewhere argue convincingly against, was that once a table reached a basic level of steadiness and so long as it turned at the right speed that the cartridge was the key variable. I was also assuming that most so-called "mid-fi" vintage tables (Thorens, Dual) had already solved these table stability problems, so that there's was no need to upgrade my table (unless I wanted to enhance my turntable envy).

Sidssp suggests upgrading the table if and when I can invest about $800 into one. I'm wondering what table (with arm included) will provide me a clear sonic enhancement compared to my TD-320? Thanks.

Winegasman, Actually the art of making turntables has progessed markedly since the days when the Duals, Thorens, whatever, ruled the market. I won't list all of the possibilities, however a couple of the big ones are the removal of the motor from the plinth and the use of a platter with substantial mass to control rotational stability. If you are seriously interested in upgrading your rig, I would start from scratch, or as a reasonable compromise assuming that you have normal budget concerns, buy a modern table that is already set up with an arm. I'm very partial to the principals being used by Nottingham and they have such a table which costs about $1000 (last I heard) including arm, called the Horizon. Add a cartridge and then you can start thinking about diminishing returns from high priced rigs. There is nothing wrong with what you have now, and its apparently serving you well. As I said earlier, save your $300 and, if you are serious, read about whats possible and then decide how its best for you to proceed.

Agree with Newbee. The thorens cannot keep up with newer designs. I heard a Michell GyroSE with newest DC motor absolutely slaughter a thorens in every conceivable category. It was not even close. The thorens is good for what it is, but there is better and it is worth it if you have the money and desire to seek it.