The main problem is that the integrated tonearms for these decks were designed for very high compliance cartridges that were all the rage on Japanese consumer decks in the late 70s/early 80s. This greatly limits the availability of cartridges that will work well on these tonearms.
Tons of high compliance cartridges available NOS on ebay from brands like grace, Stanton, Pickering, ADC, Sonus, Sony etc. All of them are MM or MI, some of them are amazing. I'm buying those cartridges myself all the time.