Streetdaddy, your room is already about as vibration rich as they come and your vibration-sensitive components are already probably saturated with air-borne regardless of their location. In other words, does it really matter if it's raining cats or raining cats and dogs? In either case, within a few moments you're going to be soaking wet. The same goes for your components.
Besides, even if you were able to minimize the destruction caused by air-borne vibrations, you would still have to contend with the constant bombardment of internally-generated vibrations induced by power supplies, motors, etc.
Hence, the only cure is to install a platform that properly redirects the captured vibrations away from the chassis' before they can start dissipating inside. Up 'til now, they've been primarily trapped within. Remember that vibrations are captured in a moment in time but they can only dissipate over an extended period of time. Much like the pluck of a guitar string.
And since it's raining cats and dogs in your listening room, it really should not matter where the bulk of vibrations are coming from whether it's low frequency bass notes or female vocalists, or a higher frequency picolo as they all generate vibrations and all are captured at the component over and above the internal power supplies and internal motors.
So without a proper cure, it should not matter where in the room (or even outside the room) the rack is placed and unless you have a rack as big as a large tree trunk, there should be little to no interference with focus, imaging, soundstaging, etc.
That said, I'd suggest placement between the speakers for shortest cable runs and creating a visual symetry / balance in the room and for the most convenient remote control.
Hope this helps,
