Composition rules for B&W aren't really much different from with color, just have less to manipulate. Sometimes this helps when drawing attention, sometimes it hurts. Personally, I like the first (uncropped) one. I like the skylight, and its lines tend to play nicely with the other diagonals going off into the distance. Also seems to "frame" the image. I also like the lone guy's reflection in the window. The uncropped one gives me more a feeling of the large empty space, and the one person moving through it.