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: What Katy Did
First Installment Wins: Many people know about What Katy did, but few know of the two sequels involving her, and even less know that Clover got her own book too.
Fixer Sue: Katy has her moments, but Cousin Helen and Clover are the worse for this.
Les Yay: Tons of it, given that the girls are constantly showering one another with kisses. Of course things were different back then, but the implication remains.
Between Katy and Cousin Helen
Then she (Katy) tumbled down by the sofa somehow, the two pairs of arms and the two faces met, and for a moment or two not a word more was heard from anybody.
Mary Sue: Clover and Aunt Helen are the worse offenders, Katy only has her moments as her flaws are very openly pointed out in What Katy Did.
Purity Sue: Cousin Helen is described as being part angel for how kind and loving she is. She was left crippled after an accident as a young woman, insisted her fiancÚ leave her so that he could have a full life without her, and he ends up living next door to Helen with his new wife and little girl. Cousin Helen remains sweet and generous throughout it all; and they even name their new daughter after her.
Suetiful All Along: Katy. The author even mentions that Katy will grow out of her plain features to become a beautiful young woman.
Values Dissonance: Clover is complimented endlessly by having a waist as 'small as a pin', but when Phil grows up thin due to getting sick in his early teens, it's only ever shown in a negative light.
The author is incredibly rude about the English people; they're portrayed to be idiots with no love of classical literature, and Americans are considered sophisticated in comparison.
While Katy in her pre-teen years is regarded as endearing, there's no doubt that she's regarded as in need of fixing. And how is she fixed into the perfect American woman of the period? By being crippled and confined to one room for four years! Unfortunate Implications abound.
Disabled people are expected to be more or less rooted to the spot (Katy has a wheelchair, but the idea that it might be used to take her beyond her bedroom doesn't seem to occur to anyone, ever- let alone the idea that it would help for her to have a downstairs room, rather than be cut off from her whole huge family upstairs). They just have to be beautiful and uncomplaining at all times, no matter how severe their pain or frustration, or, Helen says explicitly, nobody will love them. It's Inspirationally Disadvantaged Type C or nothing.