I don't read much unless I'm sick, because I can't put a book down and end up short on sleep. As a teenager, I went though at least 3 novels a week, and often one a day. But the last few have been Jack Reacher novels. They're decent reads, my only real complaint is the author's tendency to fiddle with geography (or more likely his slim grasp of it,) which sets off the alarm bells in my internal GPS.
I've been through all the Clancy stuff, Dick Francis is surprising good ( I lean more towards the techno-thrillers,) Michael Crichton, the earlier (more believable) Jake Grafton books by Coonts. Haven't read any in a while, but Grisham and Turow write good legal thrillers. If you've not read Steinbeck, you should, and beyond just Of Mice and Men and Grapes of Wrath, his short works are just as good. Most of that is fairly mainstream.
Then you get into Asimov, which is very wide ranging from non-fiction to sci-fi (I wish we had someone today with his gift for writing on particle physics.) Laumer's Retief series pokes serious fun at the folly of diplomatic protocols, among other topics. I know reading is very personal taste, but any of the top 25 writers in Sci-fi are well worth the read. From the strangeness of Philip K Dick to Adam's Hitchhiker comedy or Heinlein's thought provoking stories about cultural issues. Of course Stephen King should get a mention, although his earlier works (say, Needful Things and earlier) are better IMHO.
And non-fiction is even more of a personal taste than fiction, as it almost requires some prior interest to be readable and not sleep material. Ignition! by John D. Clark is my latest read, the story of the development of rocket fuels. You can find the pdf for free.