These are sweet! The banding on (2, 2)'s (where top-left is (1,1)) forehead where it meets the hair bothers me. Try breaking the bands up a bit.
With the palette, that brown thats third from the bottom, maybe swap that for a grey? I get the feeling that could be more useful, since there's no greys at all! I think you'd be able to use it for AA on the previously mentioned forehead, as well as add contrast to the shadow on (1, 1)'s face.
Do a wizard and a thief! I'm so original, I know.