The reason for the pose? I wanted a common dynamic topic between the three--something which forced me to consider perspective more. Jumping turned out to be fun as well, just like when many of us were younger.
Thanks, David! The pen tool got me addicted to SAI, since its pressure curve and edge smoothing were similar real nib pens. If you ever get the chance (with dual-booting Windows or a separate PC), give it a try: [link]