I like the yellow colour cast, and I don't think it's underexposed. An accurate representation of the colour, and losing the shadows would kill the mood of the shot. I don't know whether you wanted to get the whole of the bill in focus, but you could stop down a little to render the top right hand corner of the bill sharp, if that's what you're after. The object in the top right hand corner of the shot is a little distracting, too, but overall, I like this shot, well done.