Good, but...
Before I get into details, I want to mention that I watched this thinking it was something else entirely. Not knowing it was part of a series, I won't detract from the score because I didn't know what was going on. With that said, here's what I think.
The voice acting is the stand-out of this flash, better than most on Newgrounds. The visuals are well drawn as well, however the animations were too stiff. It's odd to think that you would draw every detail and barely animate them other than "bobbing" when they walked and lip-syncing. But, my real issue here is with the Spartans themselves. First off, they're the top tier in military training; obedient and loyal to a fault. Even if left stranded, they wouldn't hate the corps because they believe they are part of something bigger than themselves. Secondly, as in another post, they're far too young. Believe it or not, Master Chief in Halo was in his early forties. Also, they're overall appearance doesn't fit their characters, as they would all probably have short hair and scars of some sort. My biggest issue however, is with the main character. He keeps mentioning that he has a family; I assume that this was before he became a Spartan. This is horribly incorrect. Their training to become Spartans began at the age of six and they have never left the field of battle since.
However, this is your take on science-fiction. I'm not saying your interpretation is wrong, but that's how I feel.