Recently I was watching Arrested Development, and I noted that if I compiled a list of my Top 20 favorite sit-com characters, then that show would probably have four of them. I haven't given too much thought to the list yet, but coming up with five of my all-time favorite characters is easy. Keep in mind, this list is strictly for live-action TV shows, and I will eliminate every show with puppets so all of The Muppets, ALF, and characters from Greg The Bunny won't clutter the list. Also, shows with "character actors" like WWE and faux-reality shows like "The Hills" are eliminated because, otherwise, Shawn Michaels and Lauren Conrad would be a given to make the list with minimal rationale.
Since I can edit posts later, these first few are in no particular ranking (alphabetical order by surname IRL).
Michael Bluth (Jason Bateman)
Arrested Development was one of the first American TV shows to rely on a cast of abject human beings with virtually no redeeming qualities. At the center of the mayhem of their selfishness and stupidity, however, was straight-man Michael Bluth as the family's voice of reason and social conscious, and Jason Bateman tops the short list of actors who are genuinely funny in a straight-man role in my opinion.
Eddie Finnerty (Kevin Corrigan)
While Grounded For Life was hardly a memorable show, the family was Catholic, so I have a bias (even if they were NOT a remarkable Catholic family). Even before Gob Bluth, Kevin Corrigan was blending stupidity with selfishness together so well as Eddie Finnerty that it was almost impossible to determine whether his lines were written to represent the character's true opinion or an excuse to further his immediate cause. Of course, the logical answer is that nothing he said was "true" because he was a fictional TV character, but that character was so expertly conniving that I still have some doubts.
Cliff Huxtable (Bill Cosby)
Between the saccharin families of early television and the abject lifestyles in modern television, '80s television had Cliff Huxtable, who naturally blended the traits of an ideal husband/father with those of the easily irritable man of the house. He was as fatherly as Mike Brady with moments of frustration resembling Al Bundy, creating a family sit-coms that defied generational limitations.
Alex P. Keaton (Michael J. Fox)
The initial marketing pitch behind Family Ties was "cool parents, lame kids," and over-achiever Alex P. Keaton fit the character so perfectly that his lamest qualities were often his best. He was often selfish, always serious, and rarely sensitive, but the writers of the show maximized his minutes and turned him into one of the most endearing TV characters of all-time, objectively and subjectively.
Chandler Bing (Matthew Perry)
The cast of Friends had to wear several hats as the term "dramedy" entered the American lexicon during the show's run. Although he fell short on drama, Chandler was versatile in his comedy because his comedic timing on punchlines was nearly flawless, and conversely, his straight-man reactions were equally effective. If I ever rank these characters by preference, then expect Chandler Bing to sit atop as #1.
Uncle Jesse (John Stamos)
The broken-family comedy Full House is the punchline of many jokes these days, but at its start, it was a strong cast and solid writing. The entire male demographic was present among down-to-Earth dad Danny Tanner, funny-and-sincere Joey Gladstone, and cool-and-carefree Jesse Katsopolis. John Stamos did more than portray his character on the show, he virtually became him (from allegedly dating his TV wife Lori Loughlin to changing the character's surname to match his own Greek ancestry).
Honorable Mention: Barney Stinson (Neil Patrick Harris), Jack Tripper (John Ritter), Roseanne Conner (Roseanne Barr), Darlene Conner (Sara Gilbert), Zack Morris (Mark-Paul Gosselaar), Kevin Arnold (Fred Savage), and (tie) Paul & Jamie Buchman (Paul Reiser & Helen Hunt).