Some SF titles for you to consider
Stirlingdraka,
You are a difficult person to suggest reading material for. Let me summarise. You like Philip Dick but you didn’t like Asimov. Dune sounds too much like fantasy to you (I agree it is more a fantasy) but you like Bradbury? You don’t like hard SF but you did like Reynold’s the Prefect and H G Wells – this one is really confusing. Possibly a slight interest in military SF? Lastly you do not seem to have enjoyed Ultima. You said ‘new science fiction’ but I wasn’t sure if you meant new to you or written recently?
Hmmmm?
Well we could start with military SF. The granddaddy of them all is The War of the Worlds. I assume you have read it as it is Wells. The two seminal works of military SF are Heinlein’s Starship Troopers and juxtaposed to it Haldeman’s The Forever War based on his experiences in Vietnam. Much of everything published in the field since is homage or shameless plagiarism of one of these books. Exceptions that are worth reading include Protector by Niven which has a nice take on relativistic warfare, Greg Benford’s Great Sky River, Excession by Ian M Banks and lastly The Genocides by Tom Disch in which the human race lost.
Your taste for Bradbury suggests you might like something well written, a little poetic and symbolic. Use of Weapons by Banks, Shikasta by Doris Lessing, The Dispossessed by Ursula LeGuin, Flowers for Algernon by Daniel Keyes, Sarah Canary by Karen Fowler or Canticle for Leibowitz by Walter Miller Jr. should all suit you.
Going on your taste for Philip Dick I would suggest some existential material. A Case of Conscience by James Blish and The Sparrow by Maria Russell are full on Catholic theological works. I’d include The Quest for St Aquin with them too but it is only a short story. Lem’s Solaris would probably suit you as would the first two books in Simmon’s Hyperion Cantos, Fahrenheit 451 and Greg Bear’s Blood Music (which is a little on the hard side). You may find Hannu Rajaniemi’s the Quantum Thief bonkers in a similar way to Dick but it is very hard SF and quite pretentious. I think Clarke’s Childhood’s End belongs here as does Anderson’s Tau Zero, Sheffield’s Between the Strokes of Night and Pohl’s Gateway.
As you liked the Prefect I would suggest another two Reynolds books, Century Rain and Terminal World, these are less hard SF than most of what he writes.
On the basis of your taste for Wells who wrote The Time Machine I would recommend two fine books on time-travel by Connie Wills, Doomsday Book and To Say Nothing of the Dog. Tim Powers The Anubis Gate is also about time-travel and a very good story but might be too far into the fantasy camp for you?
Recently written (say since 2000) books you might like include Stross’ Saturn’s Children, Ken MacLeod’s Learning the World and Wilson’s The Chronoliths (his earlier Darwinia is much better). To be honest not a lot of good SF has been written in the last 15 years. There has been some excellent fantasy but that does not seem to be to your taste.
What else? I shall just throw in a few of my own favorites and hope they hit the mark. Half Past Human and The Godwhale are the definitive works on overpopulation, Brave New World said most of what needed to be said about eugenics, Aldiss' Heliconia trilogy presents an interesting perspective on ecology, A Fire on the Deep by Vernor Vinge is in part about transcendence and in part about interesting aliens, Joan Vinge’s Outcasts of the Heaven belt features a Demarchy, Varley’s Titan is a jolly romp in a living thinking world, Neuromancer is the definitive Cyberpunk novel, The Female Man by Russ is the definitive feminist SF novel but The Gate to Women’s Country by Sheri Tepper is better and lastly there is Pohl’s Dystopia Jem.
I hope that was some help?