clonecommander, if I understand you question correctly you are under the assumption that some of the holo figure's might have parts that react better than other coppies the same figure? and that the main part your questioning is the middle torso and the shoulders of this figure?
the problem isn't that it might be a defective part in this single figure, it's the type of plastic and the type of mold they used for that specific part. The middle torso section of the iron man figures is a two piece, clam-shell hard plastic. where as the rest of the figure is made from the softer, pliable rubbery plastic that is molded in a single solid piece. The slight difference in material shows up under the blacklight because the harder plastic doesn't react as well.
as for the shoulders I supose the issue there is two-fold. The position of the UV bulb is below the figure so it could be shadow issues, OR the shoulder pads are not as reactive to the UV light.
Based on these issues I believe that EVERY copy of this figure will have the same glowing parts, with approximately the same intensity (depending on the light sorce of course).
but as for the diorama I plan on making it look alot like tony's garage and place the best of the armors in there in a two story display.... as well as work on a plain clothes rhodes and pepper to include in the dio...