cute character
u should give it color the white is boring
ur rendering is just kind of bevelled instead of having strong light and dark forms with self-shadowing.
u have
staircase banding on arm and bottom of shoe but avoided it in other places (avoid it everywhere).
try avoiding dark to light pure blue and plain yellow. try to vary the hues to make them more interesting using
hue shifting.
for details like the yellow skull u don't need black outlines