imo gestures are like emotions though body language, what you see is an animation trick or exaggeration called "stretch and squash" you see it in any animation, so yes gestures can be drawn funny
try to draw with a single line don't draw over your mistakes, the stiffness that you see are that some poses even though you see them as straight with no movement, there's some nuance there, try and observe carefully where the model puts their weight
