The Beano/WMG

The characters in the Bash Street Kids are all strange because they're insane, and they're insane because they looked at Plug's face.

 * Come on, it makes sense. In addition, Plug is insane either as a result of seeing his own face in a reflective surface, or because he can never see his face as every surface it gets reflected in instantly shatters.
 * Then how come Cuthbert and Teacher are sane?
 * Teacher arguably isn't particularly sane. He appears to be quite dotty and in one comic was shown to obey every sign he reads, so perhaps that's how his insanity manifests itself. The same could be said for Cuthbert occasionally. Or perhaps Cuthbert's insanity, like Teacher's, manifests in a different way, in this case his obsessive swottiness.
 * Do you count bad entries the creators don't admit exist as canon? If so, The Beano Video says Plug is an archetype.
 * To be fair, the monks that are implied to look exactly like him don't talk.

Daisy in the Crazy For Daisy strips is an Unreliable Narrator

 * Basically she's a classic Tsundere towards Earnest, hence why his less reliable qualities are exacerbated (the parts where she isn't around are her guessing at what was going on). The alternative is that this is a children's comic strip about a girl with a Stalker with a Crush interfering with her life at every turn....

Daisy's surname

 * We know Ernest's surname is Valentine, but what about Daisy's? I think it's Daisy again, in reference to the love song "Daisy Bell".