Wondering which lead actors and actresses people think are the most talented. To be clear, I mean in terms of acting talent not your favorite. You can have an actor you like for numerous reasons but they’re average in terms of acting. Whereas a great actor is one who consistently leaves an impact in each one of their works. 

I’ll start:

Seo In Guk: Even though he started off as a singer, I think he has proved his acting talent as well. Watching so many dramas, different roles tend to blend together for me.  But for him, I can remember scenes from each one of his dramas. I love that he’s acted in all kinds of roles.

Gong Hyo-jin: She is such a natural actress. I‘ve love the fact that she can do both comedic and dramatic roles. She isn’t the most glamorous actress but commands attention in whichever role she is in.

I like Gong Hyo-jin, but my favorite actress is Shin Hye Shun
https://mydramalist.com/people/7194-shin-hye-sun

She has demonstrated a lot of breadth in her talent. I've watched the following series where she's the lead:
- Mr. Queen (she's proving how versatile she is here)
- Angel's Last Mission: Love
- Thirty But Seventeen
- My Golden Life (stellar performance in that series)

Her characters are very different in all of those.


My favorite male actor is Kim Won Hae.
https://mydramalist.com/people/4553-kim-won-hae
Why? This guy is always in support roles, but the thing is he's in so many series that I've grown quite fond of his characters... and he always plays a strange character and is funny. He's like in every 3rd of 4th series I watch.

But if I have to select a "main role" actor ... after watching Flower of Evil I really like Lee Joon Gi... great performance, best probably I've seen for a kdrama male lead.
https://mydramalist.com/people/207-lee-joon-gi

Jo Jong Suk. 

A marvelous, outstanding , natural actor.

Here is my list of top actors/actresses:

  • Kim Myungmin  - just watching him in Beethoven Virus ans Behind the White Tower just the evidence i need
  • Jo Seungwoo - he can just take over the scene in his presence and portrayal
  • Jeon Doyeon - she is queen, and I am so glad she is coning back to dramaland
  • Song KangHo - i still want him to do comedy roles, but for all his character roles he has been brillint
  • Kim Haesook - she is just soooo awesome. For a woman of the okder generation, the way she can give life to characters is just so brilliant
  • Goo Doosim - a actress that I wish was so that she can play more roles and give the younger generation a run foe their money
  • Gong Hyojin - i love her and i do think her hit dramas speajs for herself 
  • Gong Yoo - i think is my biasness talking but i do love him acting whether its the conedic roles or the silent breaking point scenes
  • Namgoong Min - he is definitely is the actor who has slowly mastered his way to thespian experience/potential
  • Jo JinWoong - signal. Its that one drama that just speaks so much about him 
  • Song YoonAh - she is briliant and so subtle yet memorable
  • Lee YoungAe -another queen and always on point
  • Lee ByungHun - this man is charisma and gravitas walking. He takes a role and just makes it so mesmerizing
  • Hwang JungMin - carries a variety of roles to amazing level
  • Ha Jungwoo - my ultimate bias!!!



In the younger generation:

  • Yoo AhIn - he can do any role. He has that look and repertoire that just pulls you in.
  • Ryu Junyeol - his presence speaks to the many rolws he did and be as memorable in each one.
  • Shin Hyesun - versatility is in SHS. She can do type genre and be effective
  • Lee Seol - she has very little acting gigs, but in the ones she did she rose above even against veterans
  • Park JungMin - definitely lives up to being the blue chip of chungmuro
  • Kim Taeri
  • Kim SooHyun
  • Kim Hyanggi
  • Kim Dongwook

Without a doubt Lee Seong Kyeong, she amazes me with her acting skills, shes literally a shapeshifter as well, like i had no idea she was in cheese in the trap. I feel like she could play any role tbh and nail it she has never dissapointed me w her acting skills

Imho impact and talent are quite subjective and depend on a viewer. Those that I consider as talented are also my favourites.So:

Chae Soo Bin - I think that she is very good and versatile actress. In "I'm not a robot" she can do so many face expressions that I sometimes can't believe that both Aji3 and Ji Ah are played only by herself (and I saw that many times). She can easily tell everything without single word. In other dramas I saw, she was great as well.

Kim So Hyun - She surely has great talent and the impact on me as well. She is also very versatile and charming actress. 

Yoo Seung Ho - His face expressions in "I'm not a robot" were priceless + best aegyo that I saw. 

There are surely many other that I have not seen yet.

Without an doubt I find Park Seo Joon a really good actor. And obviously Choi woo shik is amazing.

Jo Jong Suk is also really great.

Seo In Guk or Park Seo Joon
Both  are fabulous in terms of acting. I don't think these two actors need any explanation.
 
I find acting of actress Kim Go Eun so natural. In all her dramas she has done till now, her roles were quite different and challenging. She can do some stunt as well :')
 Her dramas -
Cheese in the trap
Goblin
The king eternal monarch.

Deff adding kim so yeon  to the list her acting is immaculate

Kang Ha Neul

Lee Je Hoon

Nam Goong Min

Shin Hye Sun

Kim Seul Gi

Jeon Jeong Seo

I can't think of a talented lead actor as most of them do fairly well but no one person stands above the rest.

As for lead actress, my favourite by far is Shin Hye Sun.   She is absolutely incredible.  Having watched so many Western and Eastern shows, I have never been as impressed with an actress as I am with Hye Sun.    

Every show she has acted in has left a startling impression on me.   Based on her already prodigious talent, she could have settled for a single genre and made tons of shows and gotten  more famous and rich.     But on evidence, she has taken the time to carefully select the right projects.    And all of her projects feature characters that she has never played before.   It is clear that she wants to challenge herself and I admire her all the more for it.    As a testament to her dedication, she had even trained many months until she could pull off being a ballerina in Angel's Last Mission: Love.     And judging from her tearful acceptance speech in a 2018 award which she received for her role in My Golden Life, getting to where she is now was not an easy route and she undoubtedly faced many disappointments and rejections on her way to making it as an actress.   

The only thing that puzzles me is how I could have missed seeing this wonderful actress so late.   I only got to know her through her role in Mr Queen which she knocked it out of the park.   I look forward to her future roles with eagerness and anticipation of being amazed once more.