Isolation fo SOTA TT?

I’m looking for advice regarding cones as isolation for my turntable. My SOTA Sapphire sits atop a 1 1/2" slab of marble using the stock rubber feet and mini Sorbogel (spelling?) feet beneath the marble. Would my tt benefit from using cones? Can you mix the Gel and cones or is that self defeating? Are cones all of a standard size and thread? My amp isn’t great with bass but my CeeDee player does bass a little better than the tt at times.
I’m of modest means so my budget would be around $75.00 if not less. Has anyone had positive (or negative) results with this form of isolation for a turntable?
Yes, but put the sorbogel in place of the rubber feet, and put the cones under the slab.
Ashra, get rid of the marble, as it rings, or at least completely damp the underside of it, such as with linoleum stuck to it.
Had a SOTA many years (w/ vac & flywheel).
Of possible interest to owners , my table sounds MUCH better if left on for at least 12 hours before serious listening .
I had a Sapphire which I traded for a Star, which I traded for a Cosmos. The best feet I had on the Star were brass cones from Sistrum. They screw onto the bolts for the rubber feet (which I don't really like.) They helped with the over all presentation of the music. I would get rid of the marble. I use 3" maple under the TT.

The only bad thing about the Cosmos is I cannot use the brass cones under it. They will not allow the floating sub-chassis enough room to float.