The colors!

I'd add pupils to the eyes, unless you're consciously going for that milky-eyed, fremen, guess-what-i'm-looking-at effect.

Also, i might think about ways that you can use shading and color to force a little more depth into the piece--i like the action in the figure, and the line quality is lovely, but i had to stare at it for a minute or two before i could separate the tail from the forelimb from the torso. Deepening/solidifying the shadows and defining the shirt away from the shadows will probably help with this a lot, as will thinking about the direction of the light (up and forward? Up and to the left? right and forward?) will probably sort this right out.

The general color scheme seems pretty strong. If you added a very subtle tint to the backs and whites of the figure, tho (making it, for instance, bluish white and greenish black instead of pure white and pure black), that might cause the figure to pop out from the background a little more. If you're using a computer to colorize it, that's easy schmeezy. If you're using markers, you could skip the tint on the white and simply mark over the black stripes with a marker of some bright color, which will tint the black a little. Alternately, if you darkened the buildings to more of a midtone and deepened the sky accordingly, that too might force the figure more clearly away from them.

In case you had any doubts about my feelings about this piece, i really do like it, tho. The composition is good, i like the super-focus that allows the figure to overflow the frame, the tilt energizes it well, and the pose and figure definitely catch my interest. It just took me some time to sort it out.