Recommendations

They both have a not so close family at the beginning.
Both dramas have adult characters with each person having a love life
Both of these dramas are a comedy family and romance drama
And they have a lot of plot twists

Unlike Hotel del Luna, the plot is not centered around romance(although there is some romance), but they are similar in a different way.
- Both dramas change the perspective of the viewer through unconventional ways: Hotel Del Luna uses ghosts while Prison Playbook uses prisoners. The stories of the ghosts and their path to redemption teach us many lessons about life and its value. In a similar sense, you find yourself immersed in the lives of those wrongfully imprisoned and largely misunderstood. As these dramas incorporate a new and creative way to tell their story, they both deliver outstanding effects and full emotional rollercoasters.
- While the genres are vastly different, you find that boiled down to their cores, both shows teach a lesson about growth. The character development of the leads is outstanding and highlights the importance of those around you, as well as inner stability on the journey of self discovery.
- As Hotel Del Luna deals with fate and the supernatural, Prison Playbook merely plays on misfortune and human treachery.
Overall, one would not immediately draw parallels between the two, but when comparing them in terms of basic themes, there are lot more similarities than expected.

bot The World of the Married and Misty are similar in their vibes, they have smart mature independent women, and their struggles through the makjangness of the world

both dramas kinda deal with the same things, the adult life of strong married women(?) and the cruel world they live in

there's a type of drama that's like "mature" grownup female leads? and these 2 fit that mood really well

The main story is basically the same. We have two married women that believe their husband is cheating with someone they are close with/work with. Both dramas are build up like a detective drama with the difference about not finding a murderer, but finding out who it is their husband is cheating with.

- Male and female leads were childhood friends.
- She was considered a goddess and he wasn't (in one case he was chubby and in the other one he was a thug).
- They meet again after years and whilst the female lead is doing ok, he has becomen a freaking god in work, visuals and reputation.
- The male lead becomes the female lead's new boss.
- They are both set in a work environment.
- The female lead's company is doing bad and the male lead was hired to help.
- They are about the same length (16 and 17 episodes).

DIFFERENCES:
- While in "She Was Pretty" the male lead doesn't recognize the female lead and she tries to hide the fact that they were childhood friends at all cost, in "Refresh Men" he knows exactly who she is and he decides to actively influence her life.

Similarities: The fluffy romance and and adult is dating a high schooler in both...
Though the other things are quite difficult, because of that while I was watching HSKoS, I was reminded of TLaHL.

both are about 2 friends that end up tangled up in a crime while they were preparing for the police academy

Honestly the plots have nearly nothing in common, maybe the cuteness of the lovers being together. On the other hand, the camerawork, the colors and somehow the similar classical music in the background made the vibes of THE GREAT SEDUCER remind me of THE K2.

Slow pace, calm/warm feelings.
Emphasis on joy of reading and literature, citations from books.
Male lead loves female lead since childhood.
RBB also has something similar like "the private blog posts" at the endings.

Both are about friendships and romance. Each group of friends go on summer vacation, one to the beach and one to Jeju island.

Both feature strong female leads that are intelligent and cunning. The storyline is really different and Young Blood is (in my opinion) a smarter drama, but the female leads are somewhat similar.

Both movies centers around a teacher and his/hers relationship with a student. Both are very dark and has many twists.

Both are crime dramas that have sci-fi/fantasy elements in them. In Memorist Dongbaek has the ability to see people's memories by touching them. In Voice Kwonjoo can hear voices with her excellent hearing ability.