Lovely, i realy dig the shapes you have there. I do think there's something vertical missing, a small fin or somehting might do the job i think.
As for the texture part, i don't think there's much to discuss there, just texture it and it'll be twice as strong and meaningfull in your portfolio. I had the chance to show my portfolio to Royal Winshester, which is a guy working at Microsoft Game Studio's on Flight simulator and train simulator if i'm not mistaking. He spotted a spacehip I have on my portfolio and instantly told me that he doesn't look to spaceships on portfolio's because there's no way to tell if they are right or wrong. (if you know what i mean).
and all this comming from someone with a wip untextured spaceship on his portfolio...
cheers