Upgrade TecnoDec Feet?

I recently purchased some 'decoupling gliders' from Herbie's Audio Lab and was quite impressed with the sonic improvements (partially because I was already using cones/floor protectors). This experience made me re-think the importance of proper isolation, so now I'm wondering about the most sensitive component of my system - the turntable (J.A. Michell TecnoDec).

The turntable currently sits on a very solid fireplace mantel, but the feet have a series of rubber knobs, which I fear might be introducing unwanted resonances.

Now, I'm wondering if I should replace these feet with the alternative "conical feet" that come standard on the Gyro and Orbe. Any thoughts?

Finally, if I do purchase the conical feet, would they benefit from Herbie's isolation base, which is essentially a cone/floor protector that makes use of their proprietary vibration-absorbing material.

I'm just looking for honest advice, preferably from someone who has owned this equipment and is familiar with it. Thanks!
I offer for your consideration an alternative path. Acoustically isolate the turn table with some type of acoustic screen. Here's the take. Your speakers create high levels of acoustic energy, that flies around the room, some striking all components, including the turntable/pith/cartridge. The best way to isolate the turntable is to put it in another room. I know, not very practical, but it will tell you how much the speaker energy impacts your sound. I have been experimenting with various types of acoustical screens, some made of lead wall paper. It is a work in progress. Don't forget to try some 'moon gel', used by drummers to deaden sound. Found in most musical instrument stores and only $6. Enjoy