Figgo

Both of these dramas have an Idol healing plot.
In Castaway Diva, the female lead uses her innocence and the life lessons she had learned from being isolated on an island for 15 years to heal various characters in the music industry.
The Heavenly Idol is a fantasy plot where a priest from another dimension uses his morality and empathy to emotionally heal members of a boy band (and sometimes using his divine powers to physically heal others).
The Heavenly Idol's story is much more satisfying and fun, while featuring much more interesting and likeable characters.

Both take place in the 1980s and are romantic tragedies. They also both feature protester and law enforcement clashes. Snowdrop has much better writing and overall production value. The focus in Snowdrop is more on the politics and harrowing plot rather than the romance, so it doesn't come across as a shallow, selfish, or irritating relationship. The side characters feel more cared for by the writers in Snowdrop as well.

I felt some Kill Me, Heal Me vibes while watching Link. They both have severe childhood trauma centered mysteries, a touch of fantasy, and emotional healing and closure from past trauma. Link, although a great drama, was unfortunately unable to capture the amazing charm and chemistry that Kill Me, Heal Me radiates.

I found myself comparing these 2 dramas as I was watching Extracurricular. They both have a serious, dark, downward spiral vibe. They both also have a high quality of production, great music, and both are shorter dramas instead of the typical 16 hour length. I highly prefer Strangers from Hell to Extracurricular though. The story feels more complete, I prefer the OST more, and the main characters are 2 of my favorite actors.