Harley Quinn: The Animated Series has adapted and brought to life plenty of DC characters, both the most and less popular ones. Each one of them has their unique psychology and characterization - Batman's villains, especially, bring so much to the screen.
The most refreshing element of this series is how modernized and satirical these characters are. Being comic-book-based personalities, their incoherent and most unrealistic traits are used to make the public laugh, but so does the fact that they're more relatable and in a more humanized role (meaning that they are portrayed as villains but at the same times as humans who have a phone, a house, friends, a life, etc.). Here are the most likable characters among all, ranked!
Dr. Psycho
Dr. Psycho isn't the most likable character of the series, in fact, his comical lines highlight h0w ridiculous his beliefs and behavior are. He has been an important element of Harley's gang, and he also added some pretty enjoyable and funny scenes to the show. His characterization isn't the best, overall, as it is neither relatable nor too interesting.
The Riddler
Sadly, the Riddler isn't the main character, but he still is one of the villains who makes the fans laugh and smirk the most. His personality is villainous, peculiar, accurate, and at the same time modernized and at times relatable. The jokes and scenes around his persona are some of the funniest elements of the series, for example after he was caught and imprisoned following the"Riddle U" episode. Still, being a great character doesn't make him likable!
Bane
Bane's character's purpose is mostly to bring comic relief to the show. He is the "bullied" member of the Legion Of Doom as most villains usually use or humiliate him, which is pretty ironic considering how deadly he could be if he wanted to shut them up.
We rarely see him as threatening and more often relatable, as someone looking for acceptance from the rest of the team. His jokes, personality traits, and scenes are a relevant and big part of the series' comical side. It is a usual version of the character, but being a parody, it's safe to say that it's a pretty enjoyable one.
Joker
Joker's role in the series morphed around season 2, as the writers started playing with the original and hilarious concept of Harley and Joker as exes rather than going after their usual dynamic in modern comics. Despite his evilness, Joker's quips and jokes are always some of the most sarcastic, sharp, and edgy ones. This trait is even more salient in season 2, in which he spends more time joking around and annoying Harley (and Batman).
Kiteman
Kiteman's personality is both soft and satirical at the same time. His role as a secondary villain is often at the center of the jokes around his persona - for example in the episode that highlighted the ridiculousness of his absurd rivalry with Condiment King (in the fourth episode of season 2, Thawing Hearts). He has, overall, a likable and pretty relatable personality, he's the type of character that you love to see on the screen because the fun is guaranteed.
King Shark
Another character heavily used for comical relief is King Shark. His heritage and bond with the sea world are some of the elements that made the "Bachelorette" episode (ninth episode of season 2) so fun.
He's one of the strongest and therefore, supposedly, also one of the dangerous members of the team; similarly to Bane, it just makes his character more ironic and comical when he often shows his naive and softer side.
Harley
Harley Quinn, despite being the protagonist of the series, isn't the most likable character of all. First, there is her tendency to annoy people and create messes; these traits don't make her boring or less relevant, since it's undeniable that her quirkiness and humor still make one of the best elements of the show. She is still likable, fun, and can be pretty relatable in her complexity, moreover, her quips and sarcasm never get old; however, she's too incoherent too often, always acts impulsively, and always ends up causing too much unnecessary trouble, making it hard to like her at times.
Clayface
This Batman villain is another one of the quality comical reliefs of this animated series. The show wouldn't be the same without his "acting" scenes, in which he ridiculizes himself most of the time and hardly ever accomplishes what he's supposed to.
He's still one of the funniest characters to see on screen, which is why he's one of the most likable characters of the show.
Commissioner Gordon
This version of the GFCP's Commissioner, Jim Gordon, is a pretty tragic-comical one. He's portrayed as an exhausted, sad man who struggles to keep up with Gotham's criminals and personal problems (such as his drinking or family problems). The type of humor that dominates in his scenes is one of the best and most hilarious elements of the show; it's a pretty parodical version of the character, such a well done satirical version that it might be better than all of the other characters' parodies.
Poison Ivy
Ivy is one of the few coherent characters of the animated series. She's quiet and does not care about anything that isn't about her, nature, or the people she loves. Despite being an eco-terrorist and villain, she's humanized and pretty relatable (as her characterization is the closest one to a real person's); her likability is strengthened by her sharp sarcasm, and she's often the only character who actually uses reason when doing and talking. Pamela Isley definitely is the one with the most likable personality.