Blood Knight: The best (though definitely not safest) way to climb the ranks, as the point gap between mission success and mission failure can be closed, and actually overcome, with only one or two kills. It's not impossible to get 5+ on some of the enemy-heavy missions.
Bragging Rights Reward: What's the reward for going through 30+ missions perfectly, succeeding each one, and racking up more kills than God? When you die, that character's record goes up on the "Roll of Honour", the game's high score list (which only keeps track of the scores on your computer).
But Thou Must: There is no option to refuse a mission. If you get a mission, it's going on your record, success or fail.
Critical Existence Failure: Averted, and played straight at the same time. As your ship's parts get damaged, they begin to lose abilities (turn radius, speed, missile launchers), but if all your cockpit parts are destroyed, your ship explodes violently, regardless of how much or little damage the ship otherwise has.
Critical Hit: Sort of. It's not unheard of for a ship to hit you at an odd angle, bypass most of your shields, and, by chance, destroy all of your Command Center parts, bringing you from 'full health' to 'spectacular explosion' in one turn.
Disk One Nuke: The most expensive ship you can use at the start of the game is 116 points. This has become the de facto standard point cost for ship design.
Enemy Detecting Radar: A ship part that functions directionally on the side it's installed on. They're cheap, useful, and somewhat non-essential, making them good filler for construction slots, especially when paired with extra command centers to prevent Critical Existence Failure.
Final Death: If you don't eject before your ship is destroyed, or your escape pod is shot down, your save file is deleted.
For Massive Damage: A ship is always less shielded in the rear, as rear shielding costs several times more than front or side. Thus, even a couple of weak missiles fired into a ship's tailplate can cripple it.
Fragile Speedster: The "Fear" chain of ships, which have a 70-degree turn radius and dog-fighting-favoring missiles, but almost no shields.
Glass Cannon: The "Bug" chain of ships, all of which are essentially just a large number of missiles slapped to an engine.
The Hornet, the biggest "Bug", is an especially glaring case. It has decent front shields, and some side shielding, but has only a single engine in the rear, so any shot from behind is going to seriously ruin your day, if not outright kill you.