Seeking recommendations about material, design, makers of low-lying rack for gear

Look at Symposium Acoustics Ultra amp stands though not cheap sound much better than wood.

If quality, stability, functionality, and damping are important then Sound Anchor can make whatever you need. Their heavy steel racks, stands, and platforms are bullet proof tough, internally damped with a sand mixture, and come with threaded bottoms so you can easily use their own spikes or casters, or your choice of footer, spring, etc.

If you look about halfway through the pictures on my system page, you will see a monoblock on a SRA platform that is sitting on a spiked SA stand that I repurposed from a speaker stand. If you look closer to the beginning of the photos, you will see a SA equipment rack that has a wood top platform and wood shelves I had from a former project. Those are also SA stands under my main speakers that I have supported by springs. I have been very satisfied with their work.

@ebm I will. Thank you!
@mitch2 What a gorgeous setup. This is very inspiring!

Take a look at Timbernation.com.  He makes maple racks.  Just simple, solid construction.  He has many styles and sizes, and he can do custom sizes as well.  I have two of his racks, and they have been excellent for my needs.  And his prices are very reasonable.  

@smrex13  I'm surfing the site now. It looks really great! Thanks a lot.