I'm no artist, but there are a couple things you can work on. First, you character drawing has no depth. It's purely two-dimebsional, and while that's okay in a lot of respects, you also have to give way to the fact that you character, as well as the armor they wear, have they're own curves, edges, points and angles. Making the solid body, and detailing the inside is fine, IF the armor allows it. Next, you drew it at a bad angle. I can tell you have at least moderate skill with a pencil in hand, but choosing the position and angle from which you draw a piece can make or break a drawing. I will, say, however, that you did very well with what you did. Third; color scheme. Your drawing, while good in concept, and decent in execution, is a little harsh to look at. Choosing another color scheme, one that compliments the armor your choosing, not only excentuates the silhouette, but also adds another layer of depth that you're lacking. Again, it's good, but, as with anything, it could be perfect. I'd like to see you do something like this after a couple more practices tries, because you're almost there, but not yet.