Modern culture would definitely say these ladies need an eyebrow wax.

I'm not sure standards of beauty have changed all that much.  Was there ever a time when having a giant, twisted honker was considered the norm of beauty?  Is it really just a modern problem that people are having nose jobs or would they have done the same in the 16th century if the technology were around?  I bet you they would have. If someone was considered good-looking who had a big nose, it would be despite the big nose, or because of their personality or radiance.

In the story there is one plain girl and one beautiful girl.  But the plain girl is not necessarily plain because she is tall and thin with big lips, and the beautiful girl is not necessarily beautiful because she's short and plump.  I don't think the author is setting an ideal of beauty and saying all women should be short and plump.  He's saying this particular short, plump girl happens to be more attractive than her sister.  

I actually used to know two Sephardic Jєωιѕн sisters -- before I became aware of the "Jєωιѕн problem" -- who fit this exact paradigm.  One was tall, thin and plain and the other was short and plump and with a sensual, baby-doll face and huge breasts, and she of course got all the attention.  But the tall, thin one thought that they were like twins and looked exactly the same even though they were total opposites.

If you are saying that the worship of women who have inflated lips that look like a baboon's butt is a bizarre modern trend, I'd say you're right.  Angelina Jolie's lips gross me out and they are apparently totally natural.  But other people like them.  That is what is really amazing to me, how different tastes seem to be despite that the world is becoming more homogenized.  

The real problem is idealizing external instead of internal beauty, no matter what you think is beautiful, or of simply not being able to accept yourself as you are.  But then, what about crooked teeth or women who have a furry, robust mustache?  As bad as all this plastic surgery is, no one complains about depilatories or braces, and that is changing oneself.  So there apparently are definite standards of attractiveness.  Humanity will always be like that.