Everything and More, David Foster Wallace
Gödel, Escher, Bach, Douglas Hofstadter
Collected Fictions, Jorge Luis Borges
In Praise of Idleness, Bertrand Russell
Antifragile, Nassim Taleb
The Long Way, Bernard Moitessier
Deceit, Desire, and the Novel, Rene Girard
The Wu-Tang Manual, RZA
Meditations, Marcus Aurelius
Essays, Michel de Montaigne
We Tell Ourselves Stories in Order to Live, Joan Didion
"Through the Looking Glass and What Alice Found There" - Lewis Carroll
"Dracula" - Bram Stoker
"Frankenstein" - Mary Shelly
"On Education" - Bertrand Russell
"The Hitchhiker's Guide to The Galaxy" - Douglas Adams
"Animal Farm" - George Orwell
"1984" - George Orwell
"Lord of The Flies" - William Golding
"Brave New World" - Aldous Huxley
"Gulliver's Travels" - Jonathan Swift
"The Selfish Gene" - Richard Dawkins
Siddhartha - Hermen Hesse
Narcissus and Goldmund - Herman Hesse
The Glass Bead Game - Herman Hesse
The Consolations of Philosophy - Alain de Botton
A Brief History of Nearly Everything - Bill Bryson
Politics and The English Lanaguage (essay) - George Orwell
A Modest Proposal (essay) - Jonathan Swift
Probably the most exhilarating read for me in a long while has been "The Secret Race" by Tyler Hamiliton. But don't take my word on it, read the reviews.
* Playing at the World, Jon Peterson ("Explore the conceptual origins of wargames and role-playing games in this unprecedented history of simulating the real and the impossible.")
* The Years of Lyndon Johnson (v1-4, 5 in production), Robert Caro. (If you ever wanted to see how political power actually works in the US, you can't beat this biography of LBJ, which reads like a (very long) novel.)
Ender's Game by Orson Scott Card. Don't let the movie fool you. The book is very good. It was at one point it was on the suggested reading list for the United States Marine Corps.
Alistair Reynolds is space opera done nicely (if you want to look in that direction). Chasm City stands on its own, but there are some similar works there.
Twain fits in with some of your other comments.
I really liked Patricia Highsmith with the sequels of Mr. Ripley. I also love the french book write Jean-Christophe Grangé with their beloved black novel books. Love the all of them.
Pessoa is fascinating. I believe it was he who wrote:
Poets pretend
They pretend so well
They even pretend
They suffer what they suffer.
I just read Metaphors We Live By by Lakoff, George and Johnson, Mark. It's an interesting study of how metaphors unconsciously drive thinking and perception.
Philosphical Investigations, Ludwig Witgenstein.
The Analects.
Structure and Interpretation of Computer Programs, Ableson and Sussman.
The Hamet and The Town and The Mansion, William Faulkner.
DFW - Infinite Jest
Pynchon - Really anything, but in particular Against the Day, V, and Gravity's Rainbow.
Rushdie - Shame and Satanic Verses, a lot of good other ones.
Neal Stephenson - Cryptonomicon
Gaddis - JR, hence my name.
Heller - Catch-22
Of course, it very much depends what you like. Your list contains a lot more nonfiction than I usually read in book form, for instance.
The 19th century Russians from Gogol to Chekhov are pretty much can't-lose. Turgenev's Fathers and Sons is beautiful and captures the spirit of youth.
Ford Madox Ford's The Good Soldier is a short masterpiece. The Great Gatsby is as good as its reputation says. Read Dickens if you want the essence of the English language and character. Read Kafka for the strangest articulation of modernity. Bruno Schulz is more whimsical. Borges is another whom your list suggests you should try.
If you really want to go down a rabbit hole, find Martin Seymour-Smith's Guide to Modern World Literature and browse through it to blow your mind. It covers everything and seems impossible, except it exists so it can't be.
Honest and challenging, without being sentimental.