"... so, I thought, why not?"

I didn't cover the whole surface since going any further would interfere with door insertion and removal.
 
The soundproofing (Elemental Designs eDead) also serves to cover vent holes in the panel. It's my intention to have as much control over airflow as I can without random gaps in the case.
 
Not shown is the hole I'd nibbled into each of the inside panels to pass wires through. I then cut a slit through the soundproofing, and it forms its own gasket.
 
I'd orignally planned to cover the cross-over wires with split tubing; but in the end, I've decided to let them go naked.