Jeremy - on my monitor the lower right has a hint of structure. I find it very difficult to retain subtle variations in the low tones in reduced scale web displays.
I can see a little structure in it as well, but it still doesn't look to me as if it should be there at all. Still, you're obviously not the only one to think that it's OK, so we can just agree to differ. There isn't a right answer, but perhaps you could try lightening it and see what you think.
I wonder what the same critics would make of Michael's Dawn Fog, the Front Page of this site today...
I love it: it's obvious what the dark area at the bottom actually is, it's clearly appropriate that it be there and it anchors the whole photo.
There's a devil in that advocaat...
Since it's a drink made from lawyers, that's hardly suprising.