Samus-esque?
Anyways, the things I think you need to focus on, in order of priority, are:
1 - Design. Right now, you don't have one. You have a guy with what we must assume is a helmet, and he's also wearing boots. This does not qualify! Even with the "steam power evidence" not included yet, there should be SOMEthing in the design that helps us to clearly understand this is, at the very least, a robot, and not say a Samus or a Megaman. E.g. points of articulation, gears, nuts & bolts, etc. All these things will help your design to communicate more clearly to the viewer what you intended, and they will help your design to become a unique creation instead of a generic blob!
2 - Basic Shading. Right now, you don't have any. This part takes a LOT of practice, and some very clear and focused thinking, so don't get discouraged, but DO at least try. I think
this tutorial is a great place to start! He uses clear language and very concise examples to illustrate the basic fundamentals of light.
3 - Interesting Colors. Right now, you don't have any! Use a wider array of colors to make your design stand out and read more easily. Use color theory to your advantage (reds advance, blues recede, the sky is blue so most shadows are too, shiny metal is generally reflective which is a whole big can of worms).
4 - Anatomy/Posture. As you are designing a robot, this is not super-number-one-top-priority, but because you are designing an apparently humanoid robot, you need to take these things under consideration, because our minds will expect certain proportions. Right now he's got some pretty long arms and a pretty big head, and his pose looks very awkward and uncomfortable.
