Awesome Music: The theme song makes a great rendition of "Over the Rainbow."
Broken Base: Fans are divided on whether or not this series is an improvement over the two Tom and Jerry movies based on Oz. Fans who disliked the direction of the film series enjoy seeing the characters of Oz get their own TV show, rather than a third outing. On the other hand, there are those who were hoping for the show to build on the mythology of Oz, rather than simply being a comedy inspired by the MGM film.
Jerkass Woobie: Wilhelmina is a spoiled rotten witch, but you can't help but feel bad that her aunt treats her like a minion instead of a daughter.
Les Yay: Ozma is very fond of Dorothy...a little too fond. And they can't get anymore closer in "Stuck on You". Even to metaphor levels, we stress in "Rules of Attraction" Ozma gives Dorothy a heart out of her vault as a Valentine's Day present. The heart also causes everyone (including Ozma) to fall madly in love with Dorothy. Note that this wasn't just something the series staff made to pander to the LGBT crowd, it's a slightly-exaggerated take on their relationship in Baum's original books.
The scene in "Toto Unleashed" when Dorothy thinks Toto has left her for Wilhelmina.
The episode, "Family Matters" focuses on the Woozy trying to find a family, since he's apparently the only member of his kind.
"The Wizard, the Witch, and the Crystal Ball" arc has quite a few.
In the scene where everyone escapes the crystal ball, Wilhelmina actually believes her aunt to be dead after everyone escapes the crystal ball. Even though she's their enemy, Dorothy and Ozma try to comfort her.
The reason for the Wizards return to Oz; he was a failure back in the real world, but in Oz, he was a powerful and respected ruler. You can tell how remorseful he truly is for trying to overthrow Ozma and blowing his chance at redemption.
Pretty much the entirety of "Home Away From Home," especially Dorothy and Wilhemina's genuine hug. Seeing someone as chipper as Dorothy cry will break your heart.