My sister emailed this and I'm publishing it here with her permission. I think she's brilliant, but I'm prejudiced. While some of this is more true of the drama world than the Korean one, there are some truths that do seem to play out in my experience.
So since I'm on my Korean drama kick, I thought I would try and write down some repeated themes. I realize that these observations do not necessarily correspond to real life, just like American television shows don't really represent us.
The similarities to regency novels: The male hero(s) are usually very handsome and very wealthy. This sometimes translates to also being spoiled or workaholics (depending on how they got their wealth). The girls are usually poor, sometimes ordinary looking, but tend to have lots of personality (e.g., quirky, self-reliant, feisty). Through the process of the show, the guys become more humble and realize the importance of the people around them. The women become more mellow, learn to trust, and also have more confidence in themselves.
Korean actors are masters of subtle non-verbal communication. And as you know well, silence is always an answer. It doesn't always mean no, it tends to mean whatever is the more difficult or hurtful choice.
All Korean actors, male and female, seem to be able to cry at the drop of a hat. It's actually pretty amazing. It must be a requirement during auditions.
Flirting tends to take the form of insulting each other. One of my favorite expressions is "Do you want to die?"
Dating is never straight-forward. It's a power struggle of who is needier than the other. The one who confesses first 'loses'.
When a couple or family members really fight, it quickly goes to hyperbole (e.g., I wish you never existed! or I hate you, you're the worst daughter ever!) These usually take the form of screaming matches.
Actually hyperbole and exaggeration are used quite often in all sorts of communication. Similarly to sarcasm to East-coasters.
Female villains are WAY scarier than male ones. They can skin you alive with their words and manipulate the hell out of other characters. The male bad guys tend to be gruff and bark and yell but ultimately aren't as effective.
Telling someone you like them is a big deal. 'I like you' often is the equivalent of saying 'I love you'. In direct contrast, Korean songs are the sappiest, most verbally affectionate songs I've ever heard.
Touching someone, even on the shoulder or hand, is crossing a boundary.
Historical dramas tend to have more of an emphasis on bromances. There isn't as much opportunity for the different genders to relate so the strong relationships are often between men.
Homosexuality comes up more as a topic in recent dramas, including gay characters. The portrayal is usually positive, but the language used is pretty brutal. For example, the word for gay translates as "not a man."
In three separate shows sons have referred to their Moms as girlfriends, lovers or pretended to date them. It is a teasing, affectionate, flirty relationship (they aren't actually lovers). In all three instances the Moms were widows. Since most of these shows are watched by women it makes me wonder if this is the sort of love and affection Moms wish they got from their adult sons.
Eating and food is a big deal. You show your love to someone by cooking for them and feeding them. In one scene a Mom is dying and desperately needs to go to the hospital. But she's just discovered her long lost son and insists on making him a meal for the first time instead. Affection and respect is shown by putting food in someone's rice bowl. Intimacy is putting food in their mouth.
I'm understanding more the emphasis on blood and bloodline that you've talked about. Well, I don't understand it, but I can see it's an important concept. When a child fails, the whole family fails because all of the blood is inter-connected and therefore failure was there in the parents and grandparents. Conversely, if a parent is a criminal or murderer the child's life is ruined because being a murderer is in their blood. Rich and successful people are inherently more brilliant, they are a better class of people because of their genetics. Granted, these sentiments are usually held by the villains but they are widespread and prevalent.
Anyway, I'm having fun. Here's a youtube video from one of my favorite dramas: http://www.youtube.com/watch?v=vCI4L1ZScZ0. I think one of the main reasons I like it is that the two main characters are so supportive of each other, they don't do the push/pull of a relationship that so many of the dramas do. For example, there is one episode where she gets engaged to someone else. I thought, okay, they're going to have an episode or two where he gets upset and misunderstands. Instead, the next time he sees her he says, you did it to save my life, didn't you? I like it when plot lines surprise me.
Pretty interesting, huh?