
The story is set in an unnamed penal colony. Internal clues and the setting on an island suggest Octave Mirbeau's The Torture Garden as an influence. As in some of Kafka's other writings, the narrator in this story seems detached from, or perhaps numbed by, events that one would normally expect to be registered with horror. In the Penal Colony describes the last use of an elaborate torture and execution device that carves the sentence of the condemned prisoner on his skin in a script before letting him die, all in the course of twelve hours. As the plot unfolds, the reader learns more and more about the machine, including its origin, and original justification.
One, because his writing is about much more than this theme (in which kafkesque is too frequently confused/mixed with Orwellian) but more because it pushes away his short stories and aphorisms, which I think are much, much better than his longer works – and more mystical and mysterious in nature. I'd take A Hunger Artist, In the Penal Colony, or some of the aphorisms from the Zürau book over his more famous works any day.
It's unfortunate that writers tend to be known for a single "brand" which causes off-brand works to be pushed to the side.
This is all a long way of saying that if you associate Kafka entirely with insurance administrators and oppressive bureaucracies and don't find this compelling, check out his shorter works.
http://www.arts.uwaterloo.ca/~raha/793CA_web/PenalColony.pdf
I read all those you mention and more at university. They still stick with me as books I'm very happy to have read, but never want to read again.