I do find the 301 platters ring. The original rubber mat is what I end using after trying modern alternatives, this helps a lot. What I have done recently to improve my 301 platter to add 3 x 5mm dia nitrile o-rings around the circumference of the platter. For strobe versions using 2 works well between the strobe markings. I made the o-rings from 88cm lengths of o-ring cord, this results in 28cm dia rings. You can buy ready made o-rings too.
Some have reported only subtle improvements from this tweak, in my SE and OB based system the effects were significant. Without it the sound seems slightly murky, rather like a slightly cloudy beer - still taste good though! Sounds with the o-rings are more distinct, less cluttered and more liable to "come from nowhere". Tight and controlled too. There seems greater stability (less smearing), the sort of thing you'd expect from a direct drive.