These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
True, though the morals are usually done a humorous way so that it's not too annoying (the same is true for the live-action series) and sometimes it does deviate from the norm in it's morals. In "A Witchmas Carol," which at first looks like it's going to be yet another version of A Christmas Carol where the complete jerkass ends up getting scared into being nice for the holiday season (in this case with Gem, who's more a jerkass here than in the entire series), Sabrina attempts to scare Gem into getting the Christmas spirit by casting a Christmas Carol spell. In a twist, the plan fails as the ghosts of Christmas past (Hilda), present (Zelda), and future (Sabrina) only make Gem love herself even more (even the fact that she won't be missed by anyone in her family — not even her nanny — when she dies doesn't bother her) and Sabrina discovers that she only hatched the plan because she disagreed with Gem's views on Christmas rather than as a genuine effort to change her, so Sabrina gives Gem a gift and wishes her happy holidays instead. Gem, at first, brushes off the gift, but is touched after realizing no one in her family is home with her for the holidays and Sabrina was the only person who cared enough about her to give her a present. So the moral ends up being "You shouldn't try to force someone to change, no matter how seemingly cold-hearted they are in order to save face. Instead you should try being nice to them in spite of everything else". That's one moral that you don't see in most shows like this, whether or not they do a parody of A Christmas Carol.
Don't even think about anorexia; If shrinking to the size of an ant isn't enough punishment, then General Cheesehead would like a word with you.
Foe Yay: Sabrina and Cassandra grow more and more attached to each other as the show goes on, culminating in Cassandra's Heel Face Turn at the end.
Hilarious in Hindsight: In one episode, Sabrina's teacher asks her what the ninth planet in the solar system is called. Her response: "There isn't a ninth planet. There are only eight". Cue everyone laughing at her.
That's subverted by the fact that Sabrina is often prone to jumping ahead without considering the consequences,(she does that in at least half a dozen episodes by my count) and in the case of this episode, she was so intent on having Gem's freedom and wealth that she didn't consider the consequences of Gem being a witch.
Jerkass Woobie: Alvin the Anti-Villain from the episode "Planet of the Dogs". Yes, he kidnapped Sabrina's family and yes, he is in serious need of a hug.
Jump the Shark: As soon as it moved to Sabrina's Secret Life. Getting rid of the entire cast that didn't originate from the comics and changing all the voices was a bad idea.
Recycled Script - One episode had Sabrina, out of jealousy of a better swimmer, accidentally turning herself into a fish, and she could only turn back if Harvey kissed her; this same storyline was done in the sitcom's comic book.
Some Anvils Need to Be Dropped: The one mentioned in the Christmas Episode above. Also the episode where Sabrina decides to become an adult and then quickly realises all the responsibilities that come with it. Even more poignant was the spell - if she didn't reverse it within a specific time frame then she would be an adult forever. A very powerful metaphor for how if children don't enjoy their childhood while they have it, it'll be gone before they can appreciate it.
Another episode has Sabrina making a birthday gift for Salem but, after hearing him bragging about the famous historical figures he knew, bins it thinking he'll want a much more spectacular gift instead. After a hectic episode where she tries to get the historical figures in question to wish Salem Happy Birthday on video camera, Salem finds the gift in the trash and tells Sabrina it's his favourite because of how personal it is. To the aunts and Uncle Quigley, Salem is just a nuisance that they have to take care of but Sabrina is likely the only one in the house who genuinely cares for him. The message was helped along slightly by not having the stock plot of Sabrina trying to buy something really expensive. Oh and the gift in question? A hand made photo frame with a picture of Salem and Sabrina together.