I love the piece, it's quite an eyesight.
The one thing I notice needs some work is textures and consistency. There are also a few angular problems with the robot that should have been fixed once you started to shade and define the robot.
Notice how the monsters, car, and HUD are outlined, while the people are not. If an object is to move or is to have some sort of role in the game, it should have similar characteristics as other parts of the game. Also, some outlines appear to be colored while others are pure black in areas that truly make no sense to be so dark.
I noticed on a close review that the light-grey stone wall on the buildings in the back don't quite blend right. The middle sections of wall have no texture, and that really makes them stand out from the rest of the piece, and I don't think that the walls in the very back should really "stand out."
And the most prominent sign of careless pixeling (hard to see from a first glance) is the lack of
anti-aliasing and the multitude of
banding (such as in the roof corners and on the robot's arms.)
You are a great pixel artist, and I am sure that you can become even better. Keep up the good work!
