Rhett Butler–Will die of an “accidental” self-inflicted gunshot wound shortly after leaving Scarlett.
Katie Scarlett O’Hara Hamlton Kennedy Butler Watling–Will die at age 90, having been married to Rhett Watling, the illegitimate son of Belle Watling, for 60 years.
Ashley Wilkes–Will die of age 70, having been the constant companion of Wade Hamilton for 30 years. Wade will die two days later of an “accidental” self-inflicted gunshot wound.
Gary Hobson thwarts several mob hits. The mob boss doesn’t let it go quietly, and orders Hobson dead. After several days of narrow escapes, the hitman breaks into Gary’s apartment, and waits for him to come home. Garry arrives home in the wee hours, after the Paper’s daily deadline, and the hitman completes his assignment successfully.
John Amsterdam, having blown off his one true love, outlives human civilization and goes stark raving mad after the rest of humanity goes extinct. A frozen dessicated being with only passing resemblence to a human finally expires some googol years later with the heat death of the Universe.
Elliot Stabler is convicted of perjury after a defendant he helped put away was exonerated by new evidence. Stabler gets shivved while in prison.
MacGyver dies of self-inflicted injuries sustained when he attempted to construct a plot device out of pieces of his own body.
Bo and Luke Duke die in a 15mph fender bender, because they weren’t wearing their seat belts.
*** Ponder
Well, I didn’t want to get too fan-wanky. 
Lost…the entire island blows up and they all die, just like they should have done when the plane crashed.
(Why no, I’m not watching the new season. Why do you ask?)
Abby on NCIS takes off a piece of studded jewelry to run a test, then trips and impales herself on it.
Riffing off FriarTed;
Jed Clampett dies with a smile on his face, surrounded by three beautiful escorts, having finally figured out what all that money can do for him.
His last words; “Well doggies!”
At the age of 15, Will Robinson dies of blood loss after a violent sexual assault by Dr. Smith, who has also disabled the robot. Dr. Smith dies moments later from severe head trauma after having been caught in the act by Major West.
Major West never tells the Robinson family what happened. As far as they know, Will, Dr. Smith and the Robot simply disappeared.
Honor Harrington : Dies in a space battle where she is outnumbered heavily, yet by her sacrifice victory is achieved. Her treecat Nimitz dies with her ( David Weber’s wife has demanded they die together if they die at all, I’ve heard ).
Victor Cachat : Probably something like blowing the fusion bottle on a ship he’s trapped on, crewed by fascists. AFTER he makes sure they know he’s about to do so.
Pushing Daisies
Ned and Chuck figure out how to touch without Ned killing her, have three babies, and live happily ever after, surrounded by pies.
Olive meets up with the holistic guy, and helps Ned expand The Pie Hole into a successful franchise.
Emerson finds his daughter, who is a successful opthamologist. She fixes Lily’s eye, and Viv and Lily revive their Darling Mermaid Darling sychronized swimming act.
Mulder: autoerotic asphyxiation
Scully: doesn’t
(oh, are canon answers not allowed?)
Gilligan screws up one too many rescue plans and is tied up and buried alive by Skipper and the Professor with the blessings of the rest of the castaways. When they are finally rescued, they claim that he was lost at sea in the storm that shipwrecked them.
Admiral Janeway dies in a “transporter accident” on a routine mission. While two crew members are charged and there is some talk of a “conspiracy” behind this, no evidence is ultimately uncovered and the entire thing is dropped. One of the charged crew members is demoted for incompetence, the other is allowed to resign from Starfleet.
Eddie Haskel becomes a racist cop and is killed in the 60’s race riots.
Kwai Chang Kane finally fights a villain who doesn’t move in slow motion. 
Professor Wickwire disappears into the Orb and is never seen again.
Lord Bowler dies peacefully in bed at the ripe old age of 104. (RIP Julius Carry)
Impossible. Incompetent Starfleet officers get PROMOTED, as might be indicated by the fact that Janeway made Admiral.
Sheriff Jack Carter literally disintegrates behind his desk, after years of radiation, chemical, and god-knows-what exposure on the job as Eureka’s unofficial guinea pig finally catch up with him.
Douglas Fargo pushes one button too many.
Ally McBeal: Her delusional episodes and hallucinations continued to infringe on her perceptions of the real world and increase to the point where she began to have problems reconciling the two. She was committed to an institution after having a serious episode at work, where she destroyed half her office in a vain attempt to keep the “fardnits” from getting her, while running from the dancing baby, who according to her had sprouted fangs and barbed skin.
The fardnits are apparently an insect-like infestation of beings from another dimension who usually manifested in her food, which is why she lost weight so dramatically as she was unable to eat much without interference from this delusion. Before they managed to restrain her, she had torn rents in her clothing and skin and was attempting to break one of the outside office windows by banging on it with her forehead so that she could jump.
After being stabilized and released on a provisionary basis, she eventually went off her meds in an attempt to recapture some of the fun of her formerly rich interior world. Unfortunately, she quickly fell into a downward spiral and committed suicide in order to be with Billy again. One bright note in all this is that as she plunged to her death she saw Billy as an angel come to take her with him.
Speaking of Kirk, I always saw him dying of something itchy he picked up from one of those Orion slave girls.
Falling off a bridge is a bit of a step down from that really.
The only problem with this scenario is that it’s entirely too likely.
Richard Bucket phoned the police early yesterday morning to report the death of his wife, Hyacinth Bucket. Her body was discovered in bed with signs of blunt trauma, suffocation, and multiple stab wounds. An inquest determined she died of natural causes. When asked for comment her grieving husband snapped, “It’s pronounced Bucket!” (Keeping Up Appearances)
She should die from kicking the bucket.
Andy Travis, eaten by a bear while camping
Arthur Carlson, heart attack in his sleep
John Caravella, liver failure (hepatitis C-related)
Jennifer Marlowe, multiple system failure at age 119
Les Nessman, skull fracture (fell in shower)
Herb Tarlek, patricide
Gordon Simms, hyperthermia (dance club-related)
Bailey Quarters, sexual misadventure (hentai-related)
Care-A-Lot is left deserted and abandoned after the Carebears are quickly killed off by a combition of chronic UV exposure, weather, unfortunate international flight routes and insanity, the latter being left untreated as mild personality “quirks”.
As someone already did WKRP:
**Alex Reiger ** is sadly shot dead in 1987 while driving his cab. He was robbed for $47 and some loose change.
**Louie De Palma ** changes his name and ends up serving as VP of the US from 2001 to 2008.
Elaine O’Connor-Nardo Married again, divorced again, marries a final time. She ran a successful if small art gallery in New Hope Pennsylvania until she died of ovarian cancer at the age of 72. She was a cancer survivor for 5 year though and got to see 6 grandkids growing up.
Latka Gravas His mental problems returned and he picked a fight with a large younger man on the subway and was knifed to death. He was not mourned by this time having alienated all of his friends.
**Reverend Jim Ignatowski ** successfully started a chain of Jim’s Mario’s and ended up richer than his dad. He was very happy and spent his waning years helping the poor and fighting for a cleaner environment. He died at age 70 but died happy living in San Francisco and smoking medical marijuana.
Tony Banta strangely fell into a successful acting career though always playing characters named Tony. He stayed in shape and lived to 87. He acted right up to the end playing old man Tony in a kids show that took place in NYC.
Bobby Wheeler never really made it in acting and drifted into first soft-core porn and drug addiction. He was found dead, beaten by some homophobic psychotics that also killed his John for the night. He was only 35.
**Jeff Bennett ** stayed in NYC until he retired. Never a big success but doing OK. He retired to Georgia and lived to the ripe old age of 103.
Zena Sherman married a wonderful man and lived happily ever after. She passed away at age 83 quietly in her sleep on Easter Sunday. She was mourned but also celebrated for living a good and happy life where she touched the lives of many others.
Simka Dahblitz-Gravas divorced Latka in 1985. She married a successful stockbroker and had one daughter. She was sadly killed while on vacation in the Caribbean by a Hurricane. She was only 48.
John Burns was never seen again but it is believe he went upstairs to visit his brother Chuck.