A few things...
The animation was great. But what's the go with the music? And the voice acting was terrible.
If you replaced that whole intro song with something by James Horner, you'd have win. I know you were going for that whole humanized element with the marines, as if they listen to music like that. But I just don't think it worked. And furthermore on the voice acting, it sounded like Jango Fett, and that's not a good thing.