Finally got around to an edit:
Shading is more round, and less "flat", that is to say highlights and shadows are focused less on just the edges and instead used to hint at actual forms. This is more obvious in places like the left leg.
Put the arm in a different position, redrew hands.
Feet are now on the same plane.
Redrew face to include more shadows and hollow cheekbones to reflect some age. Didn't do much with the ethnicity part though.
By the way, looking better on that latest tree. Although, I agree, the stump is looking a bit plain (unless it's a
baobab, in which case the canopy should be much flatter, but how likely is that?) Hope to see the sprite update soon!