I've never messed with glass, but I've got picture frames that have holes drilled in them so I know it can be done.

I can't think of any plastic that is clear or translucent that wouldn't show scratches or that doesn't scratch easily. Nature of the beast I guess.

I really like the light/white look of the mounting panel behind the darker wood when looking through the holes on your prototype. I suppose a nice metal piece such as copper might look nice, too. But then you've got to deal with ground issues with the jacks.

Shane