This is my very first critique, so i'm sorry if is not what you expected...
In my opinion, the colors are really vivid.
The metalic feeling that the Suit has is really awesome.
The Shadows/Lightning has a perfect 3D Simulated Vision, as well the reflexes of the suit.
The Lightning used in the Rocks are pretty realistic.
The glowing parts of the suit are great, it's seems good with the darkness behind.
The entire drawing has some Depth... Giving Samus and the Scene a really good vision and polished 3D Feeling.
Keep that incredible work, your art is just amazing!