It might be possible and I had the same idea first, but I wanted to keep access to all the connectors. The underside of the Pi board on the edges is quite crowded and I couldn't manage to arrange the pillars with the board so I ended up with the plastic bits. I know it isn't the best solution, but it worked for me
A simple design, I wonder why we haven't thought of this before? Is it because as humans, we tend to over think things like this?
I like it.
Actually the story behind the idea is very simple. I was looking at some nice clear plastic cases and wondered how to get hold of some raw material to build something similar. One of my colleges was just about to trash the CD protectors and asked me If I need them. And that was the moment when it hit me that there he stood with my case in his hands