Sorry to say it this bluntly, but the ship looks like shit.
The form is way to basic and generic.
The greeble stuff looks horrible-unoriginal, simple and has absolutely no meaning or function.
Materials/shading/lighting/compositing looks ok.
You seem to have enough technical knowledge, but a good architect/ship-designer, you are not.
If you are interested in doing futuristic architecture and vehicles i would advice to look at real examples of good structural engineering as well as modern industrial vehicle design.
Get as busy as a bee and you'll get good.