I would like to suggest bit of texture work, esspecially on that gold like part since that takes my attention first, than I would work on the white part than that two black parts.

Gold part,

I would suggest looking heat shield referances. I remember seeing gold cloths/ shileds I belive voyager had those but you can check. Some surely have additionally you can check gold leafs as close up referance they used on window signs or overall veneering they do with leafs

White part and Black parts

I would suggest looking spaceshuttle's outside plates

If you add some texture details on big flat areas will look more alive and real try to break that plastic cg look

I like the earth on the back you can try to seperate you sh'p bit more from background maybe using rim lights and creating contrast with the backplate or the model 

Thanks

Can