Recommendations

About time and The Master's Sun is similar as the main male leads are the one that stops the nightmare / Special ability of the main Female lead. Although in The Master's Sun, Gong- shil (Gong Hyo-Jin) sees the souls of dead people and Joong- won (So Ji-sub) is the one to stop Gong-Shil from seeing the dead people by touching her. Where as in About time, Lee Sang-yoon character stops the lifespan time on Lee Sung-kyung
character by just being close to her.
So The Master's Sun is closely similar to About time.

Both have a rich guy and poorer woman who seem to dog each other's footsteps with off the cuff meetings that end in (or are caused by) misunderstandings.

They both explore the topic on infidelity deeply and has Lee Sun Gyun's as the main lead, not to mention his voice (eargasm). Both can make you feel a lot of emotions, but My Wife's is more comedic. It has similar vibes on the melodrama side.

Both involve plots about sleeping with their friend after drinking. They try to move forward without damaging their friendship in both cases. Kiss the series is about college mates while You drive me crazy is more about adult relationship.

Both are really sweet Bl storys where one guy is insecure but the other guy makes him see that their love isn't wrong.

There's random elements that are similar. Both dramas have female leads that like to play hide and seek when drunk. They also both have a name game to verify compatibility between characters. The pace is also somewhat similar. I prefer Eulachacha Waikiki, but Beautiful Gong Shim is good too.

Both tells a story about growing up
Shows that beauty comes from the inside.
Touching and Loving stories with friendship involved.
Youth based and revolves around school life.

The main male leads both have a slightly sordid history. Ahn Dae Tae in Beautiful Gong Shim has a similar personality to Hedgehog in Panda and Hedgehog.

Both are about grown men around their 40s who suddenly find themselves having to take care of a teenager. They are forced to grow up and mature in order to do so as well as navigate through the hurdles of their own lives. Old Boy is more of a slice of life. Both dramas have a similar vibe.

both are healing dramas ...........................................................................................................

Both dramas have cold, brilliant male leads working on IT company, living an unsocial life and disliking romantic relationship (both for different reason).

Both are historical dramas.
Both dramas have revenge and prophecies related to the protagonists and the overthrow of the throne.

Both are about aimless boys and their awful life; their families are broken, they have anyone to trust. They end up meeting girls to be by their sides. In both movies there is some yakuza. In both they commit a crime.

Both are about aimless teens, their awful life in the countryside and their wrong decisions. Thay have a melancholic feel and show conflict between some teenagers.

Both are about school girls doing enjo kosai (compensated dating)

Bounce Ko Gals follows three girls in their new friendship. Most of the girls are already a long term gyaru and knows how to enjo kosai. It isn't a deep movie, It's more about friendship and youth.

Love and Pop follows only one girl from a group of friends that are beginnig to enjo kosai, so they do only the simple dates like go to karaoke. They are not as gyaru as the girls from Bounce Ko Gals, but they are starting to become. Love and Pop has a more melancholy aura and it gives us a moral in the end. It's more about life than friendship.