K-Drama where main character (Male Lead) is Genius or he is great at what he does.

Im looking for dramas like Doctor Stranger, K2, Yong Pal. +Romance and little bit of Drama/Action wouldn't be bad too. 

EDIT:
   I have seen these dramas: 

• Healer
• Fight For My Way
• W Two Worlds (On-Hold/Dropped)
• Descendants of The Sun (On-Hold/Dropped)
• You Who Came From The Star
• Pinocchio
• Cruel City

All of these have a strong romantic storyline:

• Healer - ML is the best man for hire in the business (he'll take any job that doesn't involve killing someone) and it's Ji Chang Wook before the K2
• Sungkyunkwan Scandal - ML is the best scholar (historical)
• Love O2O - ML is the top ranked player in a popular online game + the brightest and best looking computer science major in his university
• Live Up to Your Name - ML is the greatest doctor of oriental medicine of all time (time travel)
• Fight For My Way - ML is a top competitive fighter (slice of life / friends to lovers) 
• Another Miss Oh - ML is the top sound designer in the industry
• W Two Worlds - in his world, the ML is an olympic medal winner, rich, famous, better than the police at catching criminals, etc. (action / sci-fi / fantasy)
• Attention, Love! - ML is the top student in his school, and also seems to be the strongest
• Descendants of the Sun - ML is a member of the special forces, and this drama loves putting him in situations where he can show off his skills
• Hello Monster - ML is a leading international criminal profiler
• When a Snail Falls in Love - ML is the head of a detective squad + criminal profilers
• Princess Agents - ML is... the chinese historical fantasy equivalent of acting director of the CIA? He's a strong fighter / strategist and powerful political figure (warning - this drama ends with a cliffhanger) (chinese historical / wuxia) 
• Queen In Hyun's Man - ML is extremely smart and adapts very quickly to new situations (time travel)
• City Hunter - ML has spent his whole life preparing to take revenge / is skilled in combat, strategy, etc. and speaks multiple languages 
• You Who Came from the Stars - ML is a several-hundred-year-old alien with extensive abilities and a multitude of graduate degrees

Thanks to both of you. I add some dramas you recommended to my list (Love O2O; Live Up To Your Name; City Hunter; Surgeons; Liar Game; Queen In Hyun's Man; When a Snail Falls in Love).

• Hello Monster
• Nodame Cantabile
• It started with a kiss
• The Liar and His Lover
• Live up to your name

The Innocent Man - MC is someone with high capabilities whom has been deprived of his brilliant future, also anything he does, he shines.

Liar Game might fit what you are looking for

God's Quiz, the ML is top medical examiner. (The FL is also excellent in martial arts)

Sassy Go Go - the  ML is the best student at school

She was pretty - the ML is a skilled and successful editor

Solomon’s Perjury - the ML is smart and clever, he also plays the cello very well (I can’t remember if there is any romance here, there might be some, but it’s not the general focus)

Weightlifting Fairy Kim Bok Joo - the ML majors in swimming and is very skilled at it (although he has some problems, don’t want to spoil)

Signal - the ML is a skilled profiler (I especially recommend this show, since I didn’t think I’d like it, but was positively surprised) (there is little romance here though)