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.
Adaptation Displacement: "There was a book?" Yes there was, and it's actually very good. It's also rather strange that few people know it was based on a book since it mentions in the opening credits that the movie was based on Felix Salten's story...
The poster for the movie was a picture of the book.
Badass Decay: Depends on your opinion. Either the midquel did a pretty good job of doing this to the formerly solemn and dignified Great Prince, or it makes him more badass by boosting his Papa Wolf tendencies and having him directly take on a pack of vicious hunting dogs to save his son, all the while voiced by Patrick Stewart this time round.
Family Unfriendly Aesop: In the original novel, Bambi learns that he must live all alone to live long and safe. He learns this one from the (supposedly) wise Great Prince, of all deer.
Faux Symbolism: The scene where Bambi goes with his father after learning about his mother's death symbolizes the end of his childhood and innocence. This was exatly what Disney was going for with that scene.
It was revealed in the Making of Bambi II that the butterflies seen in Bambi's dream sequence and at the end of the movie are meant to symbolize Bambi's love for his mother in the former and his father in the latter. D'awww.
The death of Bambi's mom is one of the most famous tearjerkers in the history of film, to the point it's been parodied relentlessly in the seventy years since its release (q.v. the Animaniacs episode "Bumbie's Mom"). Watching the scene in context, seeing his mother give up her own life just for Bambi to survive, as well as Bambi being told by the Great Prince what happened to her is the cinematic equilivent of a punch to the gut.
The midquel also has a bit of well executed Tear Jerker, specifically in Bambi's dream sequence and the aftermath of the "Deer Call" scene, when Bambi finally comes to accept that his mother is never coming back.
Vindicated by History: Thanks to extremely mixed reception from critics of the time period, and the war going on at the time, Bambi, along with Fantasia and Pinocchio before it, was a huge box office flop when it first unspooled in theaters. Nowadays, it's one of Disney's most financially successful and critically well received movies.
Wangst: Bambi has this moment in Bambi II when he discovers his father was planning to send him off to live with another doe. And this is after they actually began to develop a bond with each other! And why? All because it's ''what a prince would do.'' It actually gets Bambi so upset that he tells his dad: