Footers under big heavy speakers (Stillpoints Ultra 5, Sistrum rack, Finite Elements,..?)

Revisiting isolation and coupling for my main system, I wonder if I would try better coupling devices than the large Symposium Svelte shelves (19"x24") I currently have under my Duntech Sovereign 2001s with 21" w x 35" d wooden base, weighing 360lbs each, which in turn rests directly onto wooden floor. My room was pretty lively before the isolation/coupling and I need better coupling/draining of energy for the speakers. 

What would you suggest?

I could try four Stillpoints Ultra 5 with base under each speaker or what I hope to be at least equally good and more economically is a pair of Sistrum rack platform (using AudioPoints 1.5) that measures 22.75"x 26.75" (I don't think their standard speaker stands can provide enough balance). I could buy a Sistrum SP-4 rack and use two platforms for my speakers. This would be budget wise the same if I would buy two Apprentice SP-SA-XL-4-1.5 (18"x24") as I am looking for a new rack for my second system (Home Theater). 

Star Sound seems to be a very reputable company but earns less coverage than, e.g. Stillpoints. 

The third and probably least talked about solution would be Finite Elements Cerabase but I find less buzz here on the Gon.