Shows that only had one season or less, but should have lived on for years.
My pick would be Earth 2.
The story lines were well planned out and the characters were distinct.
I loved that it was not another Sci-Fi show that depended on
half-naked women and crazy space creatures that you only saw for one episode.
I agree with most of the shows all ready listed, except "The Lone Gunman". That deserved the quick yank.
My list would also include:
"Police Squad!", a very funny show.
"Boomtown", which spread 24 episodes across two seasons. And the changes they (suggested by the network, I believe) between season one and two made things worse.
"Hawaii". Most people probably wouldn't agree with this one, but I thought it had a lot of potential.
RoboCop: The Series... Being an avid Robo fan, the series was extremely dissapointing because of the way that it was approached. The series decided to attract the young adult croud and therefore causing the series to forego the violence and grittiness that brought so much success to the first two movies. For a more in depth analysis of what was lacking check out this article : http://robocoparchive.com/misc/series-alookback.htm
I think firefly was one of the greatest shows ever and that it was treated really badly by fox. Another show I really liked was Space Above and Beyond, and fox treated that one badly as well.
FIREFLY DEFINITELY got shafted--it had a great backstory--a great cast--great plots and lively pacing! Fox had by this time (I believe)--decided that it no longer wanted to be known as the Broadcast sci-fi network--so it made no effort to support it at all!
THRESHOLD was messed over by CBS--it was fascinating--well done and had really interesting episodes and a very interesting and competent cast--but is it any surprise that CBS mishandled it? They haven't had a sci-fi hit since LOST IN SPACE--and they haven't had a DECENT scifi hit since TWILIGHT ZONE 40 years ago! CBS has NEVER felt comfortable with science fiction--and I'm convinced that there is a faction at CBS that secretly hopes any sci-fi show it debuts will tank--as a precedent to never try it again!
FATHOM was a VERY interesting show that had a lot of possibilities that were only BEGINNING to become apparent at the end of season 1--WHAT a Cliffhanger! An entire complex clears out to?god knows where?--my guess was some kind of secret subterranean base under the ocean floor--a Gigantic monster was on the loose that could take BITES out of SUBMARINES! A man's brother that seemed sure to be DEAD was communicating with him in an incredibly mysterious way! And last--but not LEAST--the final scene shows our protagonists standing at the pinnacle of a Church steeple staring out at nothing but water for miles around! With ALL THESE EXCITING POSSIBILITIES that had potential to develop into something maybe as big as LOST--they couldn't even give it an 8 episode guarantee? NO WONDER broadcast TV is losing so much ground to CABLE!!
The Lyon's Den was a pretty good show in 2003, about a law firm whose senior partner was murdered (covered up like a suicide) in the first episode. Rob Lowe was the lead character.