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.
Serious enough that Nigel Dobbyn, the artist for Billy the Cat, quit, resulting in the superhero's absence from the 2012 annual.
The redesign of Dennis' parents, making them older versions of him and thus rendering Gran pointless.
That hasn't stopped her from reappearing in the 2013 cartoon.
What they in fact did - going by some of the strips themselves - is implied that time has moved on and the original Dennis the Menace has grown up and is now father to the current Dennis the Menace. The difference is easy to see - the original Dennis had a black and red striped jersey, while his son Dennis has a red and black striped jersey!
Daniel "Danny" Deathshead and Toots from The Bash Street Kids.
Ugly Cute: Minnie the Minx can be this, depending on the artist.
Unfortunate Implications: Biffo the Bear's human aunt. Bananagirl is Bananaman's niece according to the Beano website but Bananaman is a child and his strips never show his siblings so that implies one of his siblings may have had a child and been disowned because of it. Which would also make sense as to why Bananaman never features in Super School strips.
When Bananaman ended up appearing as a regular character in the Beano (to justify his merchandise on the Beano Shop), the advert announcing this referred to him and Bananagirl as cousins instead. That fixes the sibling problem.
Although there's still the fact that Eric transforms into Bananaman by eating a banana - whereas Bananagirl just seems to be Bananagirl all the time. Different source of their superpowers, maybe?
Values Dissonance: An old comic strip featured in the 1940 annual was entitled Hard-Nut the Nigger. Also the character Little Peanut from the late 30s to early 40s who was a stereotypical poor black boy who appeared on the logo of the first issue but did not reappear on the cover when the first issue's cover was made a poster in 2010. Also the character Polly in the Lord Snooty strip looks unfortunately like a chimpanzee and the late 1950's strip entitled Pom-Pom the boy who brightens darkest africa.