I was thinking something like first off you could put the amps directly on Pods without even a short rack. But depending on what your standard is for looks you could spend a lot and have something that looks good but not be anywhere near the sound quality improvement of Pods. That is where the cheap rack with Pods comes from. I would use 3 per amp by the way not 4.
I've used them directly under components and also under racks. Directly under a component is a bigger effect. So that is what I would do for the mono-blocks. Personally I would skip the rack altogether and put the amps right on the Pods. They go by the way directly under the chassis, not under the feet. This both helps keep a low profile and also works better because the Pods are in contact with the chassis not the feet. Also makes it easier to use 3 vs 4. Totally the way to go.
Under a rack, I first put my turntable on Pods, then later got some of the really big ones to float the whole rack. This works great but is something to think about because it is after all equipment you handle. Speakers on Podiums only move when you touch them, which is not often. Racks however you touch that stuff all the time. The slightest touch and the whole rack moves. It is not anything to worry about, totally stable, but odd beyond words to see and so I mention it! My rack is so massive, at least 750 lbs, it sways crazy slow at about 1Hz. Maybe less. Anyway it definitely does work that way.
Whether it is more cost-effective to do the whole rack or individual components, hard to say. What I can say for sure, putting them under a component is a lot easier than a whole rack! I would lean component for that reason alone.
I was focused on the mono amps and would totally recommend 3 Pods under each, and skip the rack. But now I notice you also mentioned a low rack for components between the amps. This sounds a lot like what I have. The lower you keep things the better in terms of reflections. Also it is good to break things up by having them staggered in terms of distance. A wide flat rack is not so good in this regard. I actually played around with stuff like this a long time ago. Even fairly small stuff if it is flat it reflects enough to hear. Not big time, not very much at all in fact, but enough you can hear it. I had a guy over one time he noticed the imaging not as good on one side as the other, we figured out it was an LP leaned up for show. Moved it, better. One LP.
Not big, not gonna kill you, but there. Moving everything off to the side comes at a cost as well. Wire quality is huge. We have only so much money. For sure you move your gear to one side you will be afraid to spend what it costs for wire, you will cut corners on that, and this will result in worse sound than if you left the gear in the middle bought the better wire and lived with the reflections. Take it to the bank. Put your stuff off to the side if you must for looks. But don't kid yourself that it sounds better. It won't.
That said, looks matter. Not everyone wants the kind of mess I have, no matter how good it sounds. I am sick, and probably should be committed. But everyone knows that already.
