the nailgun's insane, but the perspective of it is great! I prefer to change weapons into immortal stuff. try to guide your forms with more cubes and boxes as a "ripcage" around your object.
For example: If you try to draw a hand, you could draw a line around all fingers (Matthew Archambault called it "the containment system"). That's thinked in 2D. But as you did for your perspective figure drawings you could use it the same in 3D and sculpt the figure part after part out of the boxes and later you only have to erase the help lines of the boxes. Keep on drawing. See you at the spartan threads.