First of all: Nice approach.
Suggestions:
I`d love to see you revealing a storyline that explains why the Alien are so furious. As in Space 2063 (aka Space: Above & Beyond), where it turned out that a human company has provoked the interstellar war) or something that prevents you from the classic stereotype Humans Good - Aliens evil - nothing between.
2. Nice segments, partially VERY NICE shaders on that. Try to keep the Components (the metal pillars) on par with the other surfaces to avoid a "broken" feeling.
3. Lights & Light Mapping:
Here you kill some of the otherwise promising atmosphere. You have lights without obvious light sources - this is a no-go, as on a subliminal level the player will ahve always the feeling "something is wrong here, it lacks a beleivable environment.
Make light sources, make them obvious. If the light comes from the stars outside, place them outside the ship in a location that could be assoziated with a bright star on the skymap. And turn the lightmapping on then!