I think a start would be something simple like a subtle, vertically-striped background. Think linen-textured letterhead (the operative key word here being "SUBTLE"). It has a "corporate" feel to it and sort of implies the concept of wealth. I would add it to the plain box on the right and, so it doesn't look alone and out of place, add it to the other box that is the same color. So, in the first example, that would be the light tan boxes, and in the second and third, the yellow boxes.

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...for all have sinned and fall short of the glory of God...
-- Romans 3:23

doug sanchez, creative director/lead designer