You have some great outlines here! However, they are currently dominating and setting the shape of the image. Try focusing on how you can allow shading to create the form of your image. Here is a quick'n'dirty edit. For the details, try thinking more at a pixel level rather than at a full-image level (particularly when it comes to the head and face).

- increased contrast
- added more highlights/shadows
- removed the cross-wise gun because I couldn't figure out how it was supposed to be attached to her and it was making the second arm kind of funky-looking

Watch those lines! Inner black lines make it look very cartoony, which works for me only when it's done smoothly. There are so many extra thick corners on the lines.. Also the extra black in a lot of areas interferes with the shading, and makes the piece look muddy.
The miniature dithering between two planes make it look more jagged.

Better shading would be nice, but I think this most of all needs clean up!