What Hydronium said about the shininess was pretty much what I had on my mind, so I second his critique.
The only problem I see with his feet is that his right (our left) foot is out of perspective; in this situation I think it would look better if his foot pointed towards us, and the first thing that popped into my mind when I saw his arm was
EVE (the robot on the left), so you could try something like that.

Here's an edit I made, trying to address everything that's been mentioned so far, as well as give him a more interesting palette.
Just as a tip, never work on a white background because it can mess with how you perceive the colors (same with black).
All in all, though, it's really cute and the curves make him much more interesting without making him look wonky, so good job with that.
Welcome to Pixelation by the way!