That's a pretty major thing not to do, I wonder if you can keep the same dimensions overall?
I think with a lot of work, it can work and do well, but it's largely a concept to most people in my opinion. I look forward to how you move on with this project 
I'm not sure why you're so interested in putting this in a box. This is an interest check to find out if the project is worth moving forward or not. As far as the design is concerned, it's a matter of putting a few holes in it and calling it good. I wouldn't consider it a "major" thing to doand that's not to say I haven't already though it through, because I have.
Like I said before, I'm not in a rush to start a group buy. There are many pieces to this puzzle that still need to come together, such as manufacturing, distributions, PCB sourcing, etc. I'll be working hard over the next few months to make sure I can achieve the lowest price possible while eventually delivering a solid product for everyone to enjoy. I hope you continue to follow along be excited about something that I truly feel will add value to this community.
Neat concept and slick design, but wouldn't a thick slab of aluminium not lead to freezing hands when used as a wrist rest?
That cold feel in your hands is actually coming from lack of circulation after sitting at the computer, hardly moving for hours on end.
)
Right now, the plan is to actually have a cavity inside the rest, so that there's room for any mods you might want to do. (Bluetooth? Raspberry Pie?) However, if it costs significantly more, or causes me to have to mill the aluminum in two pieces, you might see that change to being a solid rest.
If you're worried about it though, just try out a macbook. It's really not much different than that.
