I'm going to be controversial.
I think the best audiobook is text to speech.
I prefer to not filter any stories through an other person. I want the raw data from the book, without any other feelings and impressions added to the original.
Even when the author coached the narrator? I know of at least one audiobook where the author used the narrator’s voice to fill in what words on paper couldn’t
That sounds like a special scenario.
Tho I'm not sure if a book needs a narrator it can be still called a book instead of a theater piece or voice play.
It didn’t need a narrator, but care was taken to ensure a unified voice between author and narrator. Great audiobooks generally strive for something like that where the performance adds rather than detracts
This is why I said that I am going to be controversial.
Text to speech is only going to be better with time.
My most important preference is to have the text delivered without reader bias towards its contents. And that's only possible with computer speech.
Understood & I hear you. Some people's voices, candor and pace can put me right off listening, make me want the words without their voice. Unfortunately, with a well voiced & read book, I'll listen far longer than I can bring myself to focus on actual reading. Though reading the words makes them stick in memory differently, mostly better, than listening for me.