I suppose this book could have been more vague. What I mean by that is that it could have provided zero hints about where the story was headed, instead of only the most indirect of hints.
I do love Kazuo Ishiguro's writing, and it's been such a long time since I read a book by him. It may be unfortunate that I chose to listen to the audio version of this book instead of reading the digital bits because I was not as enamored by it as I may have been if I had been able to take my time over the phrasings and how the sections fit together. It's also true that the narrator of the audio version was, as does befit the novel, a very slow speaker. But, that meant that in order to listen to the whole thing in a drive to and from Chicago I needed to bump it up to 1.25x speed (sorry, Mr. Ishiguro and Mr. Horovitch).
The content itself captured my imagination. As usual, Ishiguro has added fantastical elements, and in the case of this novel he makes you wonder how many of those are true to his worldbuilding (i.e., real to this story). It's certainly likely that none of what you are reading is true! Other than the fact that there is a journey, and it's likely one with a tragic ending. I wonder if he wrote it upon the death of a loved one (or the dying of a loved one) because it has all the flavors of that kind of a tale (and I did go hear him speak about this book, but it's been a very long while since that evening).
I place the book at almost the same level as Neil Gaiman's gorgeously realized "The Ocean at the End of the Lane" (I loved Gaiman's more), meaning there's a great deal of power here, if you can tap into it. It just takes a little more work that it might for other novels.