I love how they're simplified! But maybe a bit more exaggeration in the twists could be better :)

Try doing some 30sec poses so you get the gesture of the figure with the C, S I method

I agree with @Yasmin Hladky, you are focusing on the wrong thing. You are capturing the contour (or "outline" if you will) of the body - the gesture is totally different. For example, in one image you drew the form of the breasts and another the pecs, but neither of these impact the gesture of the form (I assume - having not seen the images you used). Aim for capturing the 'lines of action', *not* the 'lines of the body'. One thing I believe is having an impact is the size of your pencil strokes - yours are small and tight. Try instead to focus on having long sweeping strokes for a whole section - less is more. If you can capture the whole leg in one stroke, go for it! The two minutes is not to try and be as detailed as possible, but to allow you the time to deliberate more on your strokes before putting them done. No shame in taking the whole 2 minutes for only a couple of lines if they perfectly catch the gesture!