Help with Humidor Dimensions

One of my hobbies is woodworking, so building my own humidor is a must-do project. I have a small home office that I smoke in so I've decided to make a wall mounted humidor below a shelf...it's wasted space anyway, accessible, and I have very little floorspace that is unoccupied so it just makes sense for me.

My question is about the depth of the humi. With the current configuration of the shelf, I have about 10 inches of depth available to work with and am wondering if that is deep enough for storing (most) boxes or should I make it deeper?

The current dimensions iI have in mind are approx 6'W X 12" to 16" H X whatever the consensus here determines.