Nice photos. Shot with a D5 too :O I haven't done much portraiture but I know it's always hammered away that the longer lenses are better because of the flattening of features, which I never quite understood. Of course the longer lenses are better at separating backgrounds, which seems to be the main reason why they are used for portraits. Nice job going against the grain. Is the vignetting from the lens or added in postprocessing?
they are seperating them cause of the depth of field "bokeh" but at the same time.. "compress and flaten" the backround.. which is actually a.good thing.
Yeah if you're really close up with a wide lens you'll make people's faces and noses look big, but get just a bit farther and they'll pretty much look normal. Headshots are definitely out unless you are going for the exaggerated effect.