Here is the beginning stages of modeling, I just wanted to see If I could recreate your vision. I'd like to know more about how you plan how showing the image. I understand the Peppers Principle, but I want to know the details, displaying and such.
In my recreation of your GameGlass I did not add anything behind the glass and camera. I wanted to talk a bit about that first.
Before I do that I want to first state that I think using plexiglass might not be the greatest idea and instead should use Lexan, a durable glass with real glass properties. It's tough, I've used it on Robobots. It also has an 88% light transmission, that might not mean much, but you were bringing up ideas like plexiglass, it's great don't get me wrong but I feel it's for the wrong application. For one, it has 92% LT (VERY CLEAR) this could mean ultra fine graphics but if the light is on your doomed. I want to also reiterate Lexan's durability. Lexan is bullet proof. no destroying it. (unless you forget to leave your GameGlass in the oven for a while....
As for your design I think that it should have a different charger, perhaps a mini USB or at least have 2 USB ports just in case you come up with a new use and need that extra port to charge and use the extra utility.
In the picture below I've just restated some of the tools you brought up in the first prototype.
As for the volume, I feel as if you should instead make it a slider. When dealing with buttons on a product a user will want to see a visual of where the volume is currently at (for obvious reasons). Replacing it with a slider will eliminate any disorientation of a volume popup on the hud.
Your idea for the mounting seemed odd. A solid plastic (or metal) piece won't fit everyone (even with an adjuster) Maybe rethink this? You could even go with good gold glasses look (though it might not hold up to the weight...)
Please keep me updated, I'm usually never interested in projects that are brought to me however seeing this one sparked my attention! Maybe pm me your skype and we could talk?