dnath,
When I bought an expensive new turntable like most I wanted to ensure it was free from the interference of external vibration. In particular, our wood floor transmits footfall to the stand like a bugger, and I have a 17 year old son who is big and stomps when he walks like Godzilla. I needed protection!
Having tested a great many types of isolation and damping material, I found nothing...absolutely nothing...came close to the vibration isolating properties of putting springs under the turntable platform. In this case I use the spring-based Townshend Seismic Isolation Pods. They are expensive for what they are, but I'm sure you can get similar results via a DIY approach finding some similar springs.
In any case, once the turntable base was placed on those springs, I could stomp all around the floor in front of the equipment stand and feel (and measure) almost nothing on the turntable. Works like a charm.
So, in other words, I'm not sure you need to concentrate on the particular turntable to take care of vibration isolation - especially for really big vibrations like close footfall - where instead it may be better to simply concentrate on making an isolation base that could do a much better job of isolating whatever turntable you'd like to use.