The study is looking good! Don't forget some more dark lines around the edges of his back, and use a soft brush (even just a tiny amount cause I know you don't like em) to blend the darker shadowy colours into the lighter ones.
With the portrait, lower her right eye a little, also make the nose stick out a little more and give her more nostril, as from this angle and the shape of the nose you should be able to see more. Where her nose flattens to her cheek you should add a little more shade. Don't forget to apply your eye studies to hers! I drew over a little bit if you wanna have a look to compare changes. Mines way to 'airbrushy' but it gives you an idea of how I'd see it.
The imagination one is looking good but he could lower his axe to rest on his shoulders more or give him bigger shoulder muscles to make up the space. His legs are just a little too big in proportion to his torso, and push them back a little so he looks like he's leaning into the axe?
You got the proportions of the face right in the SP it just doesn't look like your features haha. I think it's just the big lips that throw it off.
Or I could be wrong, but you told me to just say crits so you got what you asked
So overall i'd say you've had a pretty good day.