Loot half of the crates.
The crates that you did look in are mostly looted.
What you find is some rations (some of which you eat, you were pretty hungry) and ammo. The ones you killed were on the last rounds in looting the crates, so there wasn't much left of value to take.
The fruit of the search was one grenade, which may prove to be useful in the near future.
Also, can you loot the corpses for weapons/ammo and disguises? Thats probably unlikely, though. The enemy equipment probably has measures designed to protect against capture
Their suits are bonded with their skin. Trying to remove one would prove useless and possibly dangerous, as their weapons or armors may take parasitic action against you. You weren't briefed well by the research division so you'd better play it safe as possible.
That pistol did have some spare ammo in it, though.