As the others said, the perspective looks really strange, but everything else looks really nice. :)

the perspective looks orthographic, you should really look into vanishing points. i would also try another color for that hat (looks too close to the grass). and the color and structure of that necktie looks really like some kind of stone. i was thinking for a while if it could be a floating head coming out of stones.

that's pretty awesome but the skull seems very out of place and the perspective seems somewhat skewed.