Cyrus knows the Nevada National Guard is coming to the airfield to arrest or kill the cons, so he explains to the others how they will ambush them using beer cans and lines drawn in the sand. One of the cons asks what the rock next to the killzone represents. "That's a rock." It's played for a quick laugh. But if you look at where the rock is placed in respect to the ambush, it is the spot where Marshall Larkin intervenes and rescues the surviving guardsmen.
There is a scene in which an elderly couple is driving and stopped at a red light, and the man complains when a bird defecates on his windshield shortly after leaving the car wash, while his wife says it's good luck. The man starts cleaning it with a napkin and doesn't notice the light turn green. Just as he starts to drive, Pinball falls from the sky and crushes the front of the car. If he wasn't cleaning the windshield, he would have started moving right away, and therefore would have been crushed by Pinball's corpse. Turns out to have been good luck after all...
Why wasn't Cyrus suspicious when Poe stopped Johnny 23 from raping a female guard? Cyrus himself despises rapists but he may have known that Poe was in prison for killing someone in defense of his wife. He probably thought Poe was just being chivalrous and didn't question it since he also hates rapists.
Larkin's clearly states as Cyrus is introduced that he's thirty-nine years old and has spent twenty-five of them in American prisons despite having managed to escape twice. That means the best-case scenario for the last time he took a dump in private was when he was fourteen. No matter how bad his original crime was, prison has not lessened the threat he poses to society but increased it exponentially.
Garland Greene is free. While he might be "cured" of his psychopathy (which is implied by how lucid he seems in his final scene), there is also a chance that it's simply him having a "good" day, and when it wears off, or he gets bored, he might go back to his monstrous ways. Remember, this is the guy everyone was afraid of, only Cyrus seemed unperturbed by him (perhaps due to simply thinking they are kindred spirits).
