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.
YMMV: Charlie Chan
Designated Protagonist Syndrome: In some of the books, Charlie disappears for whole chapters, with most of the narrative. Hell, in House Without A Key he doesn't show up until chapter 7!
Ethnic Scrappy: The truly cringe-worthy appearances of black character actors Stepin Fetchit and Mantan Moreland as characters such as "Snowball" (wince) and "Birmingham Brown".
Fair for Its Day: As noted here, the series actually averted the Yellow Peril stereotype by showing a Chinese person as a good guy, but the whole thing can still be embarrassing today.
First Installment Wins: Largely averted. Charlie Chan sequels, spoofs and homages pay little attention to The House Without a Key, which in both film and prose started the Charlie Chan series (the film remains lost as of 2009, however). The "Number One Son" Henry first appeared in the novel Black Camel. Keye Luke played him in the films (in the first film, they explicitly refer to Luke's role as Henry; later installments generally preferred the name "Lee" with the exception of the 1972 animated series).