Which cone's or platforms have helped?

Put cones under everything. Your ears will be very happy. If you don't have them, already, on the bottom of your rack legs: PUT THEM THERE too. I have not compared them, but I use Audiopoints cones and am very happy with the sound. You can really go nuts with these cones and suffer the law of diminishing returns. Call Robert over at Audiopoints. He's really into resonance transference and will give you the scoop. His cones are very reasonable. You should get another 10 posts, at least, about this topic. The same people, including myself, will talk about this adnauseam...I love it, though. It's what I love about the Hi-End audio game.

I use Aurios 1.2 with their upgrade tungsten carbide balls under my CD player, and there are large gains in clarity and bass, at the possible expense of some upper-midrange forwardness and slight "steeliness." The trade-off's worth it to me (I suspect I'm actually simply hearing my preamp for what it is). Worth trying, and I'm told if you position the Aurios under a platform with the CD player on top of that, the problem diminishes or goes away. The 1.2s are noticeably better sounding than the 1.1s, by the way, and not hard to place (unlike the 1.0s).

I have tried a number of diffrent cones and pucks and my favorite so far is the Walker Valid Points.

Same as Tom (I am happy with Neuance shelving under the source gear).

I have used Neaunce for a year and half and other footers make my setup sound funky in comparison. Guess I am used to its sound, as well.

I have never tried roller bearings though. The closest thing to these (that I have tried) are little donuts, made of E.A.R. material, that have a ball bearing squeezed into the center (they don't R&R and are not the same as roller bearings).

Other footers/shelves have been: Maplshade cones (the cheap ones), DH cones, E.A.R. based footers (with/without the ball bearing), Vibrapods, hockey pucks, nail buffers (for light weight gear, under 5 lbs), suspension (hanging), MDF, Maple, Ikea Lack and Persimmon platforms.

I have also experiemented with top weighting, but did not care for the sound of this on any of my gear (with the exception of a few fly weight Bel Canto DAC's).

The Maplshade cone makes a nice record weight for my Thorens when inverted and blue tacked to a 45 rpm adapter.

I've gotten good results with Vibrapods all around, and also top weighting things like the CD player/Transport.