Sci-fi Recomendations

For an assignment for my Writer's Class course I have to read three novels of a selected genre. I have chosen Sci-fi as my choice. From here I am to do a writer's journal on one of these books and I do not know what my final selection should be. I want to keep away from books I haven't read.
I've started Factoring Humanity which so far seems interesting and so far my next picks are Hyperion and Ender's Shadow. I was wondering if there was anything better to slip in there.
I've read the Ringworld trilogy, and Protector by Niven and Ender's Game. Not much else.

Needs more Philip K. Dick.

Anything by Kurt Vonnegut.

Neuromancer by William Gibson is incredible. Though you can't go wrong with Hyperion or Ender's Shadow imo.

Very much liked Stanisław Lem, but skip Solaris and Eden.

Anything by Philip K. Dick would do you good.

Ubik

Flow my Tears, the Policeman Said

Time out of Joint

Dr. Futurity

I recommend them in that order.

Try out The Book of the New Sun by Gene Wolfe. Considered one of the best pieces of literature ever, it takes place tens of millions of years in the future, while the sun is in the last days of its life, and about to die out. Earth, or Urth, is nothing what we know it, all our past is forgotten, and magicka and far future technologies have taken over. Very abstract writing, often hard to understand at times, but absolutely brilliant.

Dune, by Frank Herbert.
An epic story of the life and political intrigue surrounding the planet Dune and the panacea substance, Spice. 


The Mote in God's Eye, by Larry Niven and Jerry Pournelle
The most original and realistic take on the future of Humanities expansion into space, and the eventual first contact.

Neuromancer, as mentioned above, is quite awesome.

Also,

Sphere, by michael crichton is crazy good.  Much better than the movie, which was mediocre at best.

I suggest the Culture series.

I particularly enjoyed Look to Windward.