They immediately kill the red shirt in the beginning for even reaching for his phaser, but Kirk multiple times in the episodes starts fights, and goes to get his weapons back, and they just keep taking him prisoner...when pretty much any other race would have just killed him. The big fight in the middle of the run that kills the village chief literally comes out of nowhere. Julie Newmar is ready to die at one point, and then wants to live shortly thereafter. You've got the cat and mouse between the Enterprise and the Klingon that's just a time waster. The Klingons block their path, but then don't do anything to stop them going back to the planet. You are correct though that McCoy is the one saving grace to this one. The Klingon cold war part is straight forward, but everything else, is absolutely a giant mess.