From my experience isolation resulted in a significant improvement in "clarity" compared to spikes. GAIA's are a great product but in my case I moved to Townshend Platforms to minimize the impact on tweeter height. Focal Scala EVO's do not provide for adjustment.
IsoAcoustics GAIA
I have IsoAcoustics GAIA II isolators installed on my Sonus faber Liuto floorstander speakers on hardwood floor. I expected some improvement and I got it. Bass is cleaned up and tightened. Stage became more clear because isolators removed a curtain made by unfocused, scattered bass. Floor and sofa vibrations almost disappeared completely. And... WAF is good. GAIAs passed my wife's inspection. Is there anybody with some experience regarding those isolators?