This caught my eye, as I just started this audiobook myself. I like it so far!
I'm a huge Stephen King fan myself, but I know I could spend forever just trying to get caught up on his catalog, so I've been dabbling in what I would consider mystery "classics" by different authors.
I read "The Maltese Falcon" by Hammett, then Agatha Christie's first Hercule Poirot book, "The Mysterious Affair at Styles", the first Perry Mason novel "The Case of the Velvet Claws", and the first Sherlock Holmes novel "A Study in Scarlet". It's interesting to see the different styles, as well as dialogue and situations that are from entirely different times and places from what we're used to.
So I might suggest that you jump around a bit to see what you like and to get a variety!