I finished watching the series pretty recently. While I enjoyed it overall, it got maddening at times, mostly because being a witch involves more nonsensical rules than contained in the entire Torah. You can never tell when someone (usually the aunts) will tell Sabrina that she can or can't do this or that, or else [insert repercussion here] will happen. And, yes, Sabrina is often not told about stuff until it's a pressing issue. Need I bring up the episode about pancake addiction? 

The entire second season dealt with Sabrina trying to obtain her witch's license (yeah...), which involved being tested at random, inopportune times by a Quizzmaster (no name given). The third season took place during the second half of her junior year (can't let her age too quickly!) but still contained Halloween and Christmas episodes ( ). It involved her having to discover the family secret, or else she can't get her witch's license, and perhaps something bad will happen (I honestly forget at this point). In the fourth season, she was finally allowed to turn 18 and start her senior year. Seasons 5-6 were college. The season 7 premiere wrapped up the cliffhanger and then skipped ahead three months after the theme song. Sabrina graduated from college off-screen. The show was recycling story ideas at that point, so it was time for it to end.

The cast was so inconsistent. Sabrina's best friend, Valerie, disappeared without explanation after season 1. Season 2 introduced Mr. Willard Kraft, Sabrina's overbearing, disciplinary vice principal (unmentioned beforehand), who stayed for the rest of the high school episodes (became principal in season 4). Also introduced was Valerie, Sabrina's new best friend. Valerie (along with mean girl Libby) were written out after season 3. Libby went to boarding school, and Valerie moved to Alaska, but the season 4 premiere dealt with her seemingly coming back to live with Sabrina, but then...nope! Way to tease the audience. Season 4 introduced Josh, a new love interest for Sabrina. Harvey was dropped after season 4, and he made only a handful of quick cameos during season 5. When Sabrina went to college, she moved into a rental house and gained three roommates, Morgan, Roxie, and Miles. Harvey started appearing again (in a recurring capacity) in season 6 and until the end of the series. Miles was dropped without explanation after season 6. Josh leaves after season 6. Both aunts left the series after season 6 (though Hilda's actor returned for the series finale). The aunts leave the house to Sabrina. She moves back home, and Morgan and Roxie move in with her. Morgan and Roxie are shown, in one episode, to sleep in the same bedroom, despite the fact that there should seemingly be enough rooms for each of them. Sabrina gets a job at a music magazine, but these extra characters are dropped around halfway through the season, when Sabrina quits her job. Around the same time, ANOTHER new love interest, Aaron, is introduced, the purpose being to do an engagement storyline that had been meant for Josh before Josh's actor left the series. Sabrina and Salem end up being the only characters to appear in every episode of the series.

All told, I like the series, but it's too chaotic. That said, I'd say Roxie is my favorite (human) supporting character. She's the best friend that Sabrina's ever had. Punky Power!