Dear @drbond : I owned/own and tested in my system with same cartridges around 25-30 diferent tonearms ( vintage/today ones but the SAT that I listened in other top systems I know ).
The @mijostyn are theoretical desirable tonearm characteristics and that some tonearms do not mimic those " ideal " characteristics does not means are bad tonearms.
Today and top vintage tonearms all came/comes with first rate not loose bearings ( ABEC 9, at least or jewel type. Both with very low friction and all with unmovable rigidity. ) ).
Normally a medium EM tonearm runs excellent and can be mated with almost any MC/MM/MI cartridge but for my fist hand experiences the 2 main characteristics for the better in a tonearm are the internal quality wiring that must be made with silver wire and second the overall tonearm damping specially at the headshell where the ssue is to " stop " the return/feedback resonances/vibrations that the cantilever will takes as fake modulations that the transducer works with.
My two tonearms in use are self/build designs for me and a close friend and yes those main characteristics are well covered.
Today, tonearms are like the cartridge: does not exist bad tonearms except by unipivots and perhaps tonearms that use wood build material that we must avoid.
Other characteristics out of the tonearm it self is that when be mounted in the TT must be totally isolated from.
Regards and enjoy the MUSIC NOT DISTORTIONS,
R.