Exquisite work! I registered after years and years of lurking just to express my admiration for it, so that should give you an idea how much I love the model!
Poulsom's & Ideas' Birds is one of my most priced LEGO possessions, and I absolutely would love to see this albatross next to it. :)
Have you thought of, rather than adding anything, just replacing some of the white plates in the underwings (say, a 12x4 and 10x1 on each side?) with black ones? Sure, it wouldn't be as intricate as the real pattern but at least they'll be two-coloured.