In this interview Martin Sheen mentions that he was too old for the role of Williard. It's amazing to me that as closely as I've watched this movie I never noticed that he was too old for the character. His role was so iconic I completely missed that fact.
Definitely should've won best picture. It's a brilliant movie. The cinematography and directing alone are worthy not to mention the star studded cast and plot.
Martin Sheen was absolutely brilliant in that role. We are all lucky that he was cast for that part because it was a work of genius that we'd otherwise have missed.
Perfect casting. A vulnerable, lost man trying to find himself. In the end he finds his fractured self staring back at him, he kills this entity within himself to become his strongest form.