For those of you who are looking for something different, why not try one or two of the novels mentioned below. Each offers an alternate perspective and narrative to the category it is listed under.

Of course, this is by no means a definite list but rather a cross section of choices.

Alien & Future Cultures

• CODE OF CONDUCT by Kristine Smith
• DUNE by Frank Herbert
• FOREIGNER by C. J. Cherryh
• GOLDEN WITCHBREED by Mary Gentle
• THE SNOW QUEEN by Joan D. Vinge

Alien Gateways

• GATEWAY by Frederik Pohl
• MIDNIGHT AT THE WELL OF SOULS by Jack L. Chalker

Alien Invasion

• THE VISITORS by Clifford D. Simak
• THE PUPPET MASTERS by Robert A. Heinlein
• CHAGA by Ian McDonald
• CHILDHOOD’S END by Arthur C. Clarke
• DAY OF THE TRIFFIDS by John Wyndham

Alt Timelines & Eras

• ACK-ACK MACAQUE by Gareth L. Powell
• EUROPE, IN AUTUMN by Dave Hutchinson
• THE LEGION PROPHECY by Mark A. Latham

Colonisation

• DESTINATION: VOID by Frank Herbert
• DRAGONFLIGHT by Anne McCaffrey
• EARTHSEED by Pamela Sargent

Dystopian

• DARWIN’S RADIO by Greg Bear
• DAUGHTER’S OF MOAB, THE by Kim Westwood
• YEAR ZERO by Jeff Long

First Contact

• ANCIENT SHORES by Jack McDevitt
• CONTACT by Carl Sagan

Futuristic Disasters

• THE ANDROMEDA STRAIN by Michael Crichton
• BEYOND THE BARRIER by Damon Knight
• BLOOD MUSIC by Greg Bear

Military SF

• EMBERS OF WAR by Gareth L. Powell
• GLORY MAIN by Henry V. O’Neil
• HUNTING PARTY by Elizabeth Moon
• ON BASILISK STATION by David Weber
• VALOR’S CHOICE by Tanya Huff
• VIRTUES OF WAR by Bennett R. Coles

Humanity Transformed

• BABEL-17 by Samuel R. Delany
• FLOWERS FOR ALGERNON by Daniel Keyes
• SOLDIER, ASK NOT by Gordon R. Dickson
• THE SEEDLING STARS by James Blish
• THE SPEED OF DARK by Elizabeth Moon

Hopefully, this will give you some ideas of what book to chose next.