Honest question about cartridge vs. turntable performance.

Curious to still see this question 40 years later.
1) the most critical quality to a turntable is its ability to turn a record without imparting or passing through vibration to the record and tonearm.A poorer turntable will collapse dynamics and raise the perceived noise level of a record surface because of vibration transmitted and superimposed on the record groove signal. Another name for this attribute is resolution
2)  a tonearm must track rigidly and accurately while encountering variations in the X and Y axis's due to record imperfections in hole centering and record height. Bearing friction should allow slow movement across the record but damp oscillation at higher speeds... if you see the head of your tonearm quivering  during routine record playback thats a problem
3) cartridges are analogous to speakers, the patent determines their "house" sound, the stylus quality determines the limit of  resolution in
that family

Its is far better to focus your investment on the turntable,get a reasonably competent tonearm and use something like aninexpensive Grado  cartridge. 

the other thing not mentioned here is the phono preamp... you can't go cheap on that... plan on spending at least $500. If you are using anintegrated unit with an inexpensive phono pre, start there or you could nothear much of a difference in upgrading a TT.