First, follow that 1984 rabbit hole if you enjoyed it:
Fahrenheit 451
Brave New World
Animal Farm

Aside from that, I enjoyed the biographical fiction "The Agony And The Exctasy" by Irving Stone. It's a fictionalized (but historically accurate) telling of Michaelangelo's life and works. If you like the psychology and drive of creativity, you'll probably like this.

For more recent works, try Tad Williams' "Otherland" series. They're a great mix of fantasy and science fiction that kind of cosplays through the styles of other significant works of fiction. He has other series, but I couldn't get in to the straight fantasy stuff quite as much.

Obligatory H.P. Lovecraft plug as well. You'll either love it or hate it, but if you do get in to it there's really nothing like it.

As a secondary recommendation to that, if you like the darker themes of Lovecraft, try the short story compilation "The King In Yellow" by Robert Chambers. It's what originally inspired H.P. Lovecraft's writing, but Chambers has an entirely different style than Lovecraft. He started out in the dark suspense genre, but ended up writing romance later in life. His writing is warmly vivid, even in the suspense stories. It's not a chore to make it through paragraphs of description like it can be with Lovecraft, and I think Chambers is adept at maintaining suspense through allusion and suspension, never quite revealing what you should be afraid of directly. His later romance writings don't have the same creative flare, I think he maybe was just trying to earn a living at that point.