Thanks for your responses. After having a good, really helpful conversation with Robert at Starsound I decided to fill the posts of the Solidsteel w/Micro-Fill, trade out the OEM spikes for AudioPoints, and get aluminum, or cold rolled steel plate to cover all five of the MDF shelves. Hope I don't have trouble finding a fabricator to make the damping plates.
I'll report back with the results. NB: My components are currently on a heavy, wrought iron console with stone shelves, so I won't be able to compare how the system sounded before the tweaks to the Solidsteel and after.