I'd recommend avoiding Fahrenheit if you want to avoid losing your sanity due to the console style of play they "forgot" to remove/change in the pc version.
Recently finished the Hyperion quadrilogy (HYPERION, FALL OF HYPERION, ENDYMION, RISE OF ENDYMION) by Dan Simmons and I can sincerely say that it's the best SF I've ever read.
If you're into fantasy I'd warmly recommend the Dragonlance saga by Margaret Weis and Tracy Hickman:
Dragons of...
Try Farscape. It's not gothic and it's not really dark, but it beats the crap out of Star Trek. Don't get me wrong, I am a Star Trek fan (well only Voyager, since TNG and DS9 suck IMO) but Farscape is far more entertaining and fun. Star Trek can be a bit sterile from time to time and becomes...