Hi guys! I'm currently writing a paper about how Korean Society is reflected through Korean dramas (mainly by the plot and the characters). Some aspects may include Korea's view on gender/sexuality, academic achievement/struggles, business, work/profession, gender inequality and discrimination, wealth gap etc. 
Since there are so many Korean dramas (and relatively I haven't watched that much), can you recommend Korean Dramas where the above-mentioned aspects were really/strongly evident? Thanks guys! Love yah!
Good Doctor: A guy who has a mental disorder but wants to become a doctor (and has the skills for it). He was discriminated by many due to his disorder and how he was indifferent to everyone else. I'm not sure if this is the type of drama you're looking for though but hope it helps!
I've also found that in a lot of KDramas, women get looked down upon compared to men in terms of strength. For example: Strong Woman Do Bong Soon, everyone didn't expect that such a small girl would have such strength within her and so the men thought it would be easy to beat her up and fight her. 
Good luck on your paper x
Misaeng! It really details how education/status affect your ability to go far in the work place and how people perceive you in the workplace. It also details a lot of different aspects of business such a bribery, contract workers vs. permanent employees, the consequences of defying your boss. It would be a really good example for that subject I think! I hope your paper goes well!
I second Misaeng. Not only that it might fit with what you're looking for, but it's also pretty realistic. Good luck with your paper! :)
Our Gab Soon. It will piss you off, though and make you frustrated with Korean society. It's a family drama, so it deals with marriage, divorce and re-marriage, kids, sex before marriage, living together before marriage, marrying for money, etc. I honestly don't know if Korean society is really like how it is portrayed, but if it is, it totally shattered my illusions. It really hammers traditional values and materialism into your head at the same time.
THANK YOU GUYS SO MUCH! THESE ARE ALL AWESOME RECOMMENDATIONS.
The first couple of dramas that came to mind which deals with realistic issues, were;

Best Wedding - It involves a News Anchor woman who gets pregnant while unmarried. It goes into the discrimination that single working mothers go through and how it effects their personal and work lives etc.

Twenty Again - 38 year old woman decides to go to college to study after having a family young. It goes into the struggles and the prejudices she faces as a older student from her fellow students/teachers and sometimes even family.

There probably are a lot more but my mind has gone blank lol. Anyhow, I hope this has been of some help...

Off the top of my head I Do, I Do.
It's Okay That's Love~! They mention mental illness and how it is often viewed in SK since the female lead is a psychiatrist! A lot of taboo subjects are mentionned in their discussions :D
White Christmas! A psychological drama that depicts the harsh school system!
The Greatest Love! It offers a view into the korean entertainment industry~ 
I Need Romance 3! There's a bit of the workplace aspect there as the female lead is working in home shopping! (No need to watch the previous installments to understand this one xD)
Also to go with Doctors if you want medical aspect - Romantic Doctor Teacher Kim! The best medical drama I ever watched tbh
I don't know if Korean society is really like how it is portrayed in the drama  since you want some rec. so here are some list.

Gender Inequality/Gender/Sexuality:

The Painter of the Wind
Goddess Of Fire, Jeongi
One Well-Raised Daughter
Coffee Prince

Wealth Gap:

Yong Pal
Ugly Alert
The Master's Sun
Shopping King Louis
Secret Garden
Save the Last Dance for Me
Protect the Boss
My Lovely Sam Soon
King2Hearts - (it also involve some politics)
Fated to Love You


Discrimination:

One Well-Raised Daughter
D-Day
Doctor Stranger
Yong Pal
Dream High
Ugly Alert
The Painter of the Wind
The Greatest Love
She Was Pretty
King2Hearts
Kill Me, Heal Me
Jealousy Incarnate
Hyde, Jekyll, Me
Goddess Of Fire, Jeongi

Academic Achievement/Struggles, Business, Work/Profession:

Cheese in the Trap
Heart to Heart
Dream High
You're All Surrounded
Hyde, Jekyll, Me
Hotel King
Hwang Jin Yi
Pinocchio
Kill Me, Heal Me
King of Baking, Kim Tak Goo
Lucky Romance
Romantic Doctor, Teacher Kim
Witch's Romance
Weightlifting Fairy Kim Bok Joo
Uncontrollably Fond
That Fool
Surplus Princess
Signal
Descendants of the Sun
Shopping King Louis
Protect the Boss


SK upholds traditions and history:

The King's Face
Empress Ki
The Eccentric Daughter-in-Law
Queen Seon Duk
Dong Yi


      -And- there are some you might like:

Biscuit Teacher and Star Candy
Birth of a Beauty
Flower Boy Next Door
Goblin
Gu Family Book
Healer
I Hear Your Voice
I Remember You
Iljimae
Miss Granny
Ode To My Father
Oh My Venus
I think all Korean dramas have more or less of these themes you are looking for. Tho whether they're realistic or not is totally another thing...

I'd say Misaeng, Good Doctor and Best Wedding might be the best ones. And maybe Age of Youth as well. 
Age of Youth, Radiant Office maybe.. Weightlifting Fairy Kim Bok-Joo, Beautiful Gong-Shim, Strong Woman Do Bong-Soon, she Was Pretty, One More Happy Ending and Drinking Solo maybe.. I'm not so sure, because they always show little aspects that you are looking for, but we don't get to know wether it works that way in real life..
Thank you guuuys! I can't personally thank you each enough! I'll check each of these dramas.