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.
Values Dissonance: Kilmeny is illegitimate, and it is a sign of Eric's love for her that it doesn't matter to him. Today this doesn't seem like such a big deal, but it would have been seen a more significant gesture when the book was written.
Purity Sue: Kilmeny is so, so perfect! Eric is so, so perfect! These pair do not have one realistic character flaw between them.