My guilty pleasure formula for a show right now is that the story revolves around an interesting premise/trope.
Some examples of what I mean based on my favourite shows:
-Twinkling Watermelon — a teenager travels back in time and meets his parents when they're young, and tries to make sure they have a better/happier life.
-18 Again — a middle-aged father suddenly becomes his 18-year-old self and goes back to high school, giving him another chance to understand and protect his family.
-Go Back Couple — a married couple gets sent back to their younger years and gets another chance to experience their lives and relationship.
-Reset — two strangers get trapped in a time loop and have to figure out how to stop a disaster.
-Undercover High School — an adult NIS agent goes undercover as a high-school student.
Additionally I love to have a gratifying love story woven into the story as is the case with all of these. Are there more shows like this? You can recommend any Asian Drama not only from Korea.