Yeah, those Vilppu exercises are very useful. Looking at your gestures, I would say to concentrate on the action lines first, when you sketch you tend to go for the contour lines first. The action lines are the implied lines that move through limbs, and any objects that have obvious length, they're also implied whenever there are convex contours.
Linear direction tends to be ambiguous, but the figure can specify the direction by the sense of muscle action, I mean to say that 'if an arm is extended then I know that it's moving forward because the tris and shoulders are active, I know there's a twist in a specific direction because one of the obliques is active.' A good example of it is in Michelangelo's "the temptation and the fall of man", you can tell where everyone's moving by the use of muscle cues, and the clarity of his linear arrangement.
Lines are are also implied as acting on contours, the arrow is the perfect example of it ------->, I know that arrows moving to the right because I follow the line through it's effect on the line at the end, which is being bent by it's force.
The kid's left arm and right torso work like the arrow. Also clarified formal directions by using Vilppu's tools.