It might also help if the walls in the store were actually darker. I know that at the local electronic stores they have dark walls so all the colored merchandise "pops" out. I suspect that in this picture darker walls would give them more of a sense of depth - as in they'd appear further away - as well as popping out the characters a bit more. One possible negative is that it may make the room seem smaller. It's just an idea - something to try out if you haven't already.

Before they made me they broke the mold!
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