Something that jumps out at me was the character's balance. Dunno if you might feel the same, but I felt he might fall over...

For texturing, you could totally push value contrasts farther, and sculpt the face and torso a bit to make it appear more textured. Also added pockets there too, which while isn't 'texturing', I feel that makes it feel more textured

Not a whole lot of texturing proper you can do at small resolution art, but you use other tricks to do that instead