Yeah, most people use the abbreviations of the term out of laziness and so, but it has been advised against using 'douji' and 'doujin' for it; the former (commonly used by Germans) actually means 'stupid', and the latter I forgot what it means, but I know it's supposed to be an entirely different word in Japanese too. :/

As for Light looking evil... generally shots from below or or above add to the intensity of just a facial expression alone, as does extra darker shading~ L is most often drawn with the camera angle directly at him by Obata? I suppose that may be to give his figure a calm appearance. Light is the one with all the intensity and agression brewing up, L is the opposite making it happen.