I feel like this is really interesting, but I also feel that determining this on a psychological basis would probably be easier with sketches and doodles, as opposed to full-artworks. There's probably tons of 'warm-up' artwork that isn't as... filtered (?) as the full-color artworks. Everyone has something they just doodle cause' they want to, be it horrible monsters or pretty ladies, just to loosen the hand for the actual work.
On this with myself, my comic is about children, and I always am afraid of this trope hitting me in particular. That, and drawing children is actually really hard for me.