Really, it should be called Some of the Greatest Short Stories. There are quite a few not included that could have been. The book could be a bit longer and still not be very long.
"Hills Like White Elephants": One of those great stories where you are just dropping into a scene from people's lives and then just as suddenly leaving. And yes, it's much more effective for never coming right out and saying what it's about. It wouldn't be the same story if it did. It's like the characters themselves do not want to utter the word.
"The End of Something": It's fine.
"A Clean, Well-Lighted Place": Another brief but powerful story that quickly but methodically ramps up the existential dread until we get the frantic nada prayer at the end.
"Soldier's Home": Unlike "Big Two-Hearted River," this story seems to be about what it is about. But it is still a powerful depiction of what living through war has done to the central character. The scene with the mom is very sad.
"The Killers": Very pulpy for Hemingway, and I do like those kinds of stories. But it isn't as powerful for me as most other Hemingway stories. But I do like the ambiguity and ambivalence.
"Big Two-Hearted River" Parts 1 & 2: The "iceberg theory." It's about someone not processing their trauma, and except for a brief recollection in part 1, we don't even get the sense that there is anything to process. The two parts are really one story and it's a great story because the focus on all the little details of Nick's tasks from Hemingway mirror Nick's own focus on what he's doing so that he doesn't think too much about what has happened to him. I am not always in the mood for Hemingway, but he wrote some pretty good short stories.