Decent enough, but not enough description. Also, hypocritical as this may seem; having someone become an ODST straight away is a tad unrealistic. The only reason the rule stating you needed experience in the marines was wavered in Memoirs is because they were desperate for new soldiers; they had no idea how many Covenant were pursuing the fleeing ship. Also, Blade may have been humouring Archer, or Farm Boy as he was known back then, intending to pass the application along to the marines. Once he saw the real name of Archer though, he had second thoughts.
Anyway, so yeah, a tad unrealistic. Also, Harvest wouldn't have an armoury, the citizens were against violence. And you should describe what's going on more, because it's like "He decided to become an ODST, so he went to the ODST office and became one. Then he met up with his new squad and they were thrown into action immediately."
Try to put in some scenic description and character in between the events occuring. And space out the lines, for example...
The Elite walked across the corpse littered battlefield, curling his lip in satisfaction. He saw a fellow Sangheili. "When will the Keelbug come to clear this mess? The scent of blood is unappealing." the first Elite asked, and the second looked over. "I don't think that way brother, the smell reminds me of the horrors of war, and how it is not to be taken lightly." the first nodded, stepping over the corpse of a human Lieutenant. "Whilst what you say me be true, it doesn't make it any less disgusting. Come, let us head back to the Phantom, my belly aches for food."
Would become...
The Elite walked across the corpse littered battlefield, curling his
lip in satisfaction. He saw a fellow Sangheili.
"When will the Keelbug
come to clear this mess? The scent of blood is unappealing." the first
Elite asked, and the second looked over.
"I don't think that way
brother, the smell reminds me of the horrors of war, and how it is not
to be taken lightly." The first nodded, stepping over the corpse of a
human Lieutenant.
"Whilst what you say me be true, it doesn't make it
any less disgusting. Come, let us head back to the Phantom, my belly
aches for food."
See what I mean?
"This one has forgotten whether it's heatsink is over capacity. It wonders whether the criminal scum considers itself fortunate" ~ Blasto, the only Hanar Spectre.