What makes a good equipment rack?

I've outgrown where all my components live and planning on building a solution myself.

I get the need for air flow around components. No turntable in my future which I'm sure have special needs.

What should I be concerned about or need to address beyond just making a solid peice of furniture and cabling accessible?
I would suggest solid construction, damping, and flexibility for different sized equipment.

I had good success with a Sound Anchor equipment stand, which is solid, welded steel with a sand filling for damping.  I currently use Sound Anchor stands beneath my monoblock amplifiers and beneath my stand-mounted speakers.  For reasons of aesthetics, I now use a purpose-built wooden furniture cabinet for my front end gear, but I have significantly reinforced the cabinet making it very heavy and solid.  Wood seems to have some inherent damping properties but I also use a variety of damping platforms on each of the shelves, including one carbon fiber Black Diamond Racing shelf and three Z-slabs, which are constrained layer platforms that originally came with a Zoethecus equipment stand.

I like the ability to adjust the shelf height for use with different equipment. My wood cabinet originally had adjustable shelves but for stability a have since mechanically anchored the shelves to the frame of the cabinet. However, I can adjust them to different heights if I need to in the future.

If you start with a solidly built stand (or rack), you can then experiment with various equipment footers (such as Stillpoints, etc.), platforms underneath the gear, and damping on top of the gear.  You can also experiment with different footers for coupling or decoupling the stand itself.  

Say, didn’t those Zoethecus platforms originally use Sorbothane for the viscoelastic material? That would certainly explain their sound. 😃 We were going to use a Zoethecus stand under Curl and Crump’s Bar-B-Q amp at the show until we discovered placing the amp on cones sounded much better. That is when I opened the Zoethecus up and spotted what appeared to be uh, Sorbothane.

Nothing beats a good rack. A solid equipment stand is a good thing too.

>>>>>You need to work a little on your stand up.
didn’t those Zoethecus platforms originally use Sorbothane for the viscoelastic material
Search me Wally, I have never taken one apart.  I believe they are constrained layers and I know the top layer is aluminum.  They are of course no longer made but people seemed to like them.  I no longer have the rack but I have three of the z-slabs.  I found the following quote at the link below.  Who knows what they mean by "phenolic, viscous damping fluid" ....is that code for Sorbothane?  Now you have me interested.  Maybe I will go take one apart.  
The heart of the Zoethecus system is the Z Slab. The hand-laid composite core consists of 10 discrete sub-layers of phenolic, viscous damping fluid, aluminum and high density fiberboard to thoroughly dissipate component resonance. This top-of-the-line 15-pound slab is perfect for heavy amps, transports and turntables.
Most likely someone straightened them out and they use some other material or fluid for the viscoelastic layer. If it wasn’t Sorbothane it looked like it. Whatever it was sounded remarkably unpleasant. When I took the Zoethecus apart at the show it was twenty years ago. My how time flies!
Speaking of racks and stands, and since you are good with underwater stuff, do you know much about the SRA folks and products?

I don’t have any experience with SRA products but you have to hand it to their marketing dept.

From their page for Virginia Class iso stand,

“Each jewel-like chassis features a custom-made nanocomposite housing. This creates the ideal coupling path between component footer and isoBASE, enabling it to drain and sink skin-effect vibration.

Under this nanocomposite skin are two of our enormously complex Raft Isolation Systems™. Each is encased in its own vacuum and calibrated to single-angstrom tolerances. It’s our most reactionary, most effective implementation ever.

Mechanically grounding this to your floor are build-specific leg assemblies. These are made of HY80 high-tensile steel, a material originally developed for the hulls of U.S. nuclear submarines.”

I just set up a brand new Sound Anchors 200 pound 5 shelf unit. I love this thing! Solid as a rock and I love the way it allows air to circulate all around my gear! It sounds terrific to boot! I still use my Iso Acoustics footers under all my gear in addition to the rack. Best rack I have ever used.
If I were starting over, and had unlimited funds, I'd get Sound Anchor stands for everything. I have their ET LFT-8b speaker stands, and love 'em. Cut some Baltic Birch plywood into shelf-size pieces, finish them with satin polyurethane (it brings out the contrast between ply layers), and use whatever isolation devices you prefer.
When I was using my Sound Anchor equipment stand, I made a quartersawn oak top shelf that really warmed up the industrial appearance.  I also made thick quartersawn oak platforms that I use on the tops of my Sound Anchor amplifier stands.  I use thin sheets of Isodamp elastomer material between the wood platforms and the tops of the amplifier stands.  The stands themselves are spiked to the concrete floor.  You can see the various stands in my system pictures.
Good info here.

Around here lots of folks milling timber. I've been considering starting with a 2-3 " thick live edge cedar plank. I was looking at some good looking 14" wide pieces that I thought would look good for the base and top shelf.

This would allow me to put the regenerator in the center of the bottom shelf flanked by the mono-blocks. I have some 3/4" rubber floor mat that I could use between the bottom plank and the floor. 

A couple of 1" thick 4/4 finished cedar boards for the middle shelves. Maybe embed a bit of angle iron to the shelves to deter sag and provide vertical support for the loads. It wouldn't be adjustable but solid and I don't anticipate changing equipment this decade. 

I'm thinking it would be rather solid and lots of mass. The stall mat towards the floor would give some isolation. 

Would I be missing anything? Always leaves that door open for mats and such as some are suggesting