Strangled by the Red String: In the spinoff Tales From the House of Bunnicula, Howie has a friend of his, Delilah, read over his books and give him criticism, most of which he ignores. They have a Vitriolic Best Friends dynamic with her constantly scolding him for writing books that focus more on Rule of Cool than telling an actual story, until the final one where he writes a Grossout Show superhero story with a shockingly heartfelt ending about his love for his friend saving her. Romantic love. Delilah is so touched by this ending that she falls in love with him on the spot and they both agree to roll around in compost together.
There's also the litter of rabbits that Bunnicula apparently sired in Nighty Nightmare. Given that'd we'd just been told about the mass murder of a bunch of vampire rabbits in the past, it would've been nice to follow that up somehow.
Tropes specific to the 2016 animated series.
Alternative Character Interpretation: Is Bunnicula truly as innocent and childlike as he appears? While some of the supernatural goings on are caused by accident and Bunnicula is usually the one to set things right in an episode, some episodes heavily imply that Bunnicula enjoys unleashing supernatural mayhem on the household just to mess with everyone, especiallyChester.
Bunnicula himself. Some find his mischievous antics endearing and adorable, others feel that he comes off as a malicious Troll and his actions border on Designated Hero territory. The episode "Garlicked" is one particularly bad example. Also, there's the idea of making him an actual vampire; either you think it adds to the supernatural aspect of the show or that it's disrespectful to the books.
Harold. Some love his laid-back, Nice Guy, lovable oaf demeanor, while fans of the book hate that he's been reduced to a bumbling side-kick to Chester when in the books, he's more intelligent and the voice of reason.
Broken Base: The TV series, for fans of the books. Some fans genuinely love the series and consider it a funny adaptation in its own right, while others hate how little respect it has for the source material, feeling it takes way too many liberties with the characters and story, such as making Bunnicula an actual vampire when, in the book, it was left largely to the reader's imagination. The base is a little less broken with people finding out that James Howe, one of the book's authors, is involved with the show, and actually approved the changes.
Creepy Cute: Bunnicula is basically designed to be this.
Fridge Brilliance: Most of the characterization changes (i.e. Bunnicula having genuine supernatural powers and Harold being a slow-witted yet well-meaning sidekick) can be chalked up to that the show is from Chester's perspective. Of course he'd make himself out to be a heroic genius right all along and beleaguered by everyone else!
Chester is an interesting case. He's not quite as naturally mean as your typical example but he's known for his scathing sarcasm as well as a tendency to take revenge to the point of becoming a bully. The episode "Chester's Shop of Horrors" especially highlights this where after mercilessly bullying Bunnicula to get back at him, he goes on an emotional rant about just how insecure he really is at the climax of the episode. There's also the fact that he constantly suffers from both physical and emotional abuse and is pretty much a ball of nerves most of the time. In another episode, he tries to put up Bunnicula for adoption to get rid of him but after hearing Mina tell someone a story about him, he's legit moved to tears and feels guilty about attempting to do so.
The ghost of Rusty Bones from the episode "Scaraoke". True, he put a horrible curse on an innocent teenage girl for butchering his song on a karaoke machine but his life was absolute hell before his eventual death.
They Wasted a Perfectly Good Plot: At the end of "Scott Free" it's implied Scott still understands the pets and still knows Bunnicula's secret, but then Scott just disappeared from the show before anything could be done with that.
