If you're into low-budget K-dramas with an opposing threat (criminal) plotline that is executed in the most underwhelming way possible, you'll like both of these.

Both of them have a male lead with trauma from a past relationship. In A Boss and a Babe, Cher's girlfriend had been abused by her dad and then killed herself because of it. In My Lovely Liar, Do Ha's girlfriend had been in a very similar situation. (won't give more information because of spoilers)

Their new partners help them get through those tough memories and feelings of guilt for being "unable to save them".

Both Theory of Love and My School President involves bickering between the male leads, a one-sided/secret crush, a no-dating rule, a fun friend dynamic, and an overall well-set vibe.

In My School President there are multiple references to Bad Buddy, for example the high school juniors from Bad Buddy having the same actors as the music club in My School President.
Both of these dramas have a frenemies/enemies to lovers trope, secret crushing, no-dating rule, ML who plays the guitar & sings, as well as just generally a similar vibe to them.

1000stars and Moonlight Chicken have a similar cast.
What they have in common is that we explore themes of miscommunication, lying, and trust. Mix is a rich kid who's helping out/working with Earth in both of these dramas in one way or another.

Both involve a ML who's in the student council. The characters are generally a lot alike, but the main character in Light on Me is quite almost the polar opposite of the one in My School President. I've enjoyed both dramas a lot, and you should definitely give both of these a chance!

If you like GeminiFourth, you should check both of these dramas out. Although in Moonlight Chicken they are solely a side couple, their chemistry and scenes are beyond adorable. Definitely check both of these out. Moonlight Chicken is more bittersweet while My School President is a lot more lighthearted, but both are charming dramas either way.

Cupid's Last Wish doesn't stand a chance against A Tale of Thousand Stars when we're talking about a great drama, but it does have some similarities. First of all, EarthMix- their dynamic is pretty much the same in both of these dramas: bickering and nagging at each other, yet caring and careful when affected by worry. Both of these also have a supernatural element as result of a car crash, as well as a misunderstanding caused by the main character's (Mix) dad. (in 1000stars it's Phupha interacting with him without Tien knowing, and in CLW it's an "unfair" inheritance)