Cool Loser: Subverted. Sabrina is not unpopular or considered a "loser". Everyone at school like her except Alpha Bitch Libby, who is just jealous of her, and Brad, who is later revealed to be a Witch Hunter.
Ditzy Genius: Sabrina is a model student and eventually gets her degree in journalism. Yet she can't help but get herself in trouble in pretty much every episode (and going to her aunts for help). See Invincible Incompetent.
Girl Next Door: Despite being blonde and attractive, Sabrina is just your average every-day girl. In one episode she learns that the other students like her because she's so down-to-earth and friendly.
Go-Getter Girl: Or at least, she becomes this as she devotes herself to her ambitions of being a journalist.
Invincible Incompetent: Sabrina went seven years without ever learning even one or two simple spells she could reliably not mess up. Notable in that there usually was no villain except for her mastery of this trope alternately causing and fixing problems.
Missing Mom: Sabrina's mother is mortal and is not allowed to have contact with her. She turns into a ball of wax if she sees Sabrina without approval from the Witches Council. In the series finale, the Witches Council does allow Sabrina's mom to attend her wedding, but demands that one of the aunts be temporarily turned into wax. Hilda volunteered Zelda and she is turned into a red candle.
Nice Girl: Despite her tendency to mess things up, Sabrina is usually well–intentioned.
Official Couple: With Harvey. A file from the X-Files Website later confirms that Aunt Irma - you know, the crazy lady with a temper that likes turning people into things - officiated the common-law wedding of Harvey and Sabrina and that they later lived in a house outside of Westbridge.
Plucky Girl: Definitely. She's always optimistic and never gives up.
Cool Aunt: Zelda is the serious aunt, Hilda is the "funny" aunt.
Flanderization: Hilda gets Flanderized from being the slightly more easy going of the two aunts to being a ditzy slacker. The best example is her music career: she goes from being a skilled orchestral violinist in the first season to having to be nagged into doing any practicing at all by her sister in the third.
(to his followers):...and I'll be the most maniacal dictator the world has ever seen! (beat) Did I day dictator? I meant leader.
Harmless Villain: He's always played for laughs and his attempt at World Domination was thwarted pathetically easily (some guys showed up and arrested him, at which point he starts sobbing).
Jerk with a Heart of Gold: He's selfish, self-centered and still wanting to take over the world... but he does have a heart. It's obvious he really cares about Sabrina (and deep down also Hilda and Zelda)
Token Evil Teammate: He's still scheming and hoping to someday take over the world. Since he's a cat with no magic powers, however, his plans are usually limited to taking advantage of others in petty ways.
Troll: Has moments of this, particular on Sabrina, though she often retaliates. One time being a GIFT when playing online chess got him into trouble as one of the players he insulted came looking for him.
Verbal Tic: "Gyeeeh?" whenever he's surprised or shocked.
His characteristic sob when things don't go his way might also count.
Vitriolic Best Buds: With Hilda and (to a lesser extent) Zelda. They drive one another nuts on a regular basis, are always sniping at one another, and at times it seems like there's no love lost between them, but on a few rare occasions they do show that they care for one another.
Hilda was actually one of his followers; they drive each other nuts because her punishment was to look after him.
Adorkable: Despite being a popular jock, sometimes he comes off as endearingly awkward.
The Bus Came Back: Left the show after Season Four, but made a handful of cameo appearances in Season Five, before he returned as a regular character in Season Six.
The Ditz: Occasionally he can be extremely clueless, but his heart is in the right place.
Give Geeks a Chance: A rare example of a female geek with a male hottie. Sabrina (Cool Loser though she may be) is the unpopular, science and math loving girl who ends up with popular jock Harvey. (Although most female geeks don't look like Melissa Joan Hart, Maxim covergirl.)
Odd Friendship: After learning Sabrina's secret, Harvey develops one of these with Salem.
Romantic Runner-Up: In later seasons. That is, until the series finale, when he and Sabrina end up together. A file from the X-Files Website later confirms that Aunt Irma - you know, the crazy lady with a temper that likes turning people into things - officiated the common-law wedding of Harvey and Sabrina and that they later lived in a house outside of Westbridge.
The Bully: She enjoys tormenting Sabrina and her friends, and calling Sabrina a "freak" as regularly as possible.
Fate Worse Than Death: In an episode where Sabrina began working as a temporary sandman and started invading people's dreams, she learned Libby actually enjoys going to high school because she can humiliate and belittle others. The next day Sabrina lied and told Libby she'd heard that she won a scholarship and would be studying abroad, out of a regular school. The mere thought of it completely horrified Libby.
Freudian Excuse: In "Five Easy Pieces of Libby", it's strongly implied that the reason Libby doesn't show compassion for other people is because it's never been shown to her.
Hidden Heart of Gold: It's been stated that Libby has yet to develop compassion or empathy for her fellow human beings, but it's been proven that she has a soft spot for and genuinely loves her grandmother, whom she goes to amusement parks with on her birthday to ride roller coasters.
Put on a Bus: He accepted a job in Prague as part of a spell to save Aunt Hilda, and he was never seen again.
Real Life Writes the Plot: The engagement and wedding storylines in Season 7 were written with him in mind. But, the actor wanted to move on to work in another series, so he was written out and the character of Aaron was created to fill that role.
Character Development: Roxie starts season 5 as an anti-social moody bitch and ends the series as one of Sabrina's closest friends.
Cute Bruiser: She's the shortest main character (not counting Salem who is a cat) but she's very tough.
Miles: God, that felt great! I’ve always dreamt of kicking in a door.
Roxie: And since I did the kicking, you can keep on dreaming.
Freudian Excuse: Roxie being the way she is gets explained in seasons 6 and 7 when we find out her mother was in prison for theft and her father and stepmother pay her no attention, resulting in her never even having a proper Christmas.
Lethal Chef: When she tried to make food for a soup kitchen. She only knew how to make starch dishes and her spaghetti managed to break the fork.
Calling the Old Man Out: During one Christmas episode, Sabrina spent the holiday with Morgan and her family. The viewers learned that Morgan's parents constantly argue with one another and show no consideration to the fact that Morgan has constantly attempted to make them happy. After talking about it with Sabrina, Morgan finally calls her parents out for their constant, thoughtless criticism and decides she's not taking it anymore. This gets her parents to realize how they've treated her and they become more considerate.