Speakers on speaker stands-isolation ideas?

How about putting a block of ballistic gelatin under each speaker? Should offer real good isolation!

That’s not a bad idea. Gelatin. As in Jell-O. Of course, you have to work out the engineering details. Speaking of Jell-O, of the major food groups Spam seems to offer the best of all possible worlds when employed as a damper. Not too hard, not too soft. And if it doesn’t work out in your system you can make sandwiches out of it.

I use Sanus 22" Steel Series stands topped with IsoAcoustic Aperta stands for isolation. Works quite well I must say.

IMO, you are approaching this the wrong way by assuming "isolation" as you call it, will yield a sound that is more preferable to you.  I'm a big fan of standmounts and I have consistently found that each speaker requires something different to adjust the sound to your preference.  You must also consider safety, as putting a speaker on a stand with no attachment subjects it to being knocked over.  But rather than think of isolation, I would first try the speaker on the stand with something like Herbie's black dots, then with Blu-tak, then with some hard interface - I've used casino chips, and see what sounds best.  Same thing with the stands.  Try spikes, try Herbie's Ebony Domes, which are also good under speakers, but allows them to move around.  I don't even think isolation is necessarily desirable.  I have found the stands to greatly influence the sound of the speaker, almost as if they are a part of it and sometimes coupling the two units as one yields the best results.  I think. 

I put some self-stick felt pads on the top of the stands, under the four corners of the bottom of the speakers, that seems to work well...in addition to filling the stand's upright with sand.