How important is an audio rack?

I have a 72" Florence Knoll Walnut Credenza that I inherited from my father who bought that and a matching shorter credenza that I use as a sofa back in my living/ listening room. It is classic mid-century design at it's best and fits beautifully in my 1916 Chicago Bungalow. See it in Virtual Systems.

My experience, having been down this road with DIY and my store-bought audiophile rack is briefly:
1)The shelving material is a lot more important than the construct/rigidity of the stand.
2)MDF is terrible.
3)This is a very particular area where people get sold theories and believe whatever they want.
4) Light 'n rigid has worked well for me, and not using a good rack is lost potential. Footers are not worth the money, IME for my system.

Caterham1700 has some good posts on the subject.

My experience with racks is minimal to the moment, but i think i need to try some of the big buck ones. That's where the improvements are audible from what i know.

i place my components on the floor ,using anti resonant devices and 1 to 1 and one quarter inch maple, about 18 inches by 13 inches.

as a reviewer, i find it easy to interchange components.

The rack/platform makes a difference. If it makes for bad vibes, it will be almost impossible to compensate further up the chain.

Anything that wobbles is not good. Things that ring, such as glass shelves, undamped metal frames are to be avoided. Too much damping also degrades the sound, resulting in a lifeless presentation.

What I like: the custom plywood cabinet in my secondary system sounds great, better than the A/V cabinet that was made of a wood particle board. I chose Mapleshade for the main system. The sound is very slightly tilted to the lower midrange with my gear. The shelves are infinitley adjusable and the racks look fantastic.

What I don't like: I hated the Polycrstal rack, but it sold fast so it must work for some systems better than in mine. It was terrilbe with tube components, sucked the life right out of them. I have a Stand design rack that has a metal frame and catilevered shelfs which doesn't sound good either. It now resides in my office with a cheap receiver.

I would lean towards Mapleshade, Cambre Core, or Quadraspire. I think it's easy to go overboard with too much hi-tech material and overdamp/isolate the music right out.