Ok, for the first one:
• Don’t ever shade with black. Sorry if that sounds harsh, but it’s a huge no no in the art community.
•Sometimes the shading is overlapping with other parts of the body which in unnecessary. Here are some of them I found:
• Instead of randomly splodging bits with the airbrush, define some of the darker tones and shading with a hard brush to show shadow. Like this:
• Shade under the chin and neck area with a darker tone of the skin colour.
• With realistic art, it’s more efficient to make the outline of what you’re coloring a darker shade of what it’s outlining. For example, if you are outlining a pink dress, outline it in a dark pink. This way it’ll make it look softer and more natural, and less cartoon-ish
• Use bright colours if you wish, but it’s always helpful to know that softer and less saturated colours are nice too
Second one:
• If you used a base, then ok. If you traced over this, then remember to trace other important aspects like sections of hair and fingers.
• Look at hoodie and shirt references to see how they are shaded. Avoid doing random splodges of the blur tool or airbrush.
• Underneath the places where the arms are, there should be shading/a shadow. This applies for the leg as well (depending on where the light is hitting the characters.)
Last one:
• Some lines are overlapping the other lines. Clean these up:
• Is her hand missing or is it just tucked under the sleeve?
• Sometimes, refining the lines so they’re sharp at the ends creates a neat and more in depth look, like this:
• There are some places where you haven’t colored properly - fill in those white spaces.
• Use a harder pen to counterbalance the softness of that airbrush/blur pen you’re using to shade.