A commonplace among authors (and common advice to those aspiring to write) is that ideas are "a dime a dozen." Meanwhile, one good idea can occupy an author for months, even years.
That's fair. No matter how well an author handles the craft of writing, or even the world-building, what sticks with most readers is the premise or the plot. The idea, that is. The inspiration side of writing, not the perspiration side.
A Really Great Idea can carry a story, even with less than stellar execution. I recently reread the Riverworld series. The careless repetition of material bugged me -- but the idea still blew me away.
How about a Really Great Style without a good idea? Can style carry a book? I don't think so. Certainly not for this reader.
(And once you do, be sure to look inside the cover. Longyear is a master. If you're unfamiliar with his work, he's perhaps best known for the novelette "Enemy Mine," basis of the 1985 movie Enemy Mine. [That said, "Enemy Mine" is not part of this collection.] In that film, Louis Gossett Jr. puts in the best performance of the Other until Andy Serkis as Gollum in the Lord of the Rings trilogy -- and Gossett had neither CGI nor motion-capture technology.)
And if you're without a key to the vault? I find walks helpful. My neighbors know that it's nothing personal when I wander past them in a daze -- that I really am in another world.
So if you'll excuse, me, I'll be off on another walk