Those are neat. I also think it would be fun to hide the hinge and put the release inside the main box. As DKL points out, I would be afraid the external release might get caught in brush and dump my stashed treasures.
One thing I noticed with the H. House Spears rifle is how many TINY knuckles he managed on that narrow lid -- the metal must be pretty thin! Also, he retained the pin by mashing down the outermost knuckles; once they are filed a little bit, the hinge barely shows in profile. Very nice touches.