The aesthetics of an exhibit is not just its appearance, but also the general impression it makes and overall experience it provides.
The point is not to make just a piece of furniture. We are anxious to make certain that the central focus of attention is firmly on the featured phenomenon, rather than being distracted by other factions. That is why all the exhibits in the Experimental Zone (the whole upper floor) now have a uniform style of casing. The consistent use of plywood and metal has a visually calming effect and is more conducive to concentration.