If you've read mangas and seen various anime or even some J-dramas, this plot wouldn't be anything new for you.
It's your typical ' A depressing broken Idol lost singing plot where the most normal/bland MC appears, blooms her life and she goes back to her routine life. That's it. '

Now where this drama loses is, Suzy's character lacks depth.
All she did was make a sad face and smoke cigarettes for 80% of her screen time.

Perhaps that's why they cast her, she fulfilled her character's personality. xD

Everyone else was good.

It was a one-time watch
Oh, I still think the manhwa writer stole this plot from a Japanese manga, usually, Koreans don't write/draw in such a setup.

This was definitely a Japanese idol theme rather than Korean.
For someone who's read and seen numerous J plots such as these, you can easily tell.
They even had a dating simulation scenario till episode 5, which was fun to explore.
You root for one girl and the writer, in the end, tricks us, after all the drama is named ' Doona '

The theme had various elements similar to ' A Star Is Born ' as well.

The SFML was the best character in this drama, played by Ha Young. (The girl is really talented)
She's worth looking forward to, the manhwa writer has focused on her in 2 episodes particularly, and she outshines the FML.

Apart from her, in the end, this drama felt superficial.

Now if you want to drown yourself in melancholy for no reason, and be sad, then you might find this drama a bit to your liking.
But that's superficial, there are many more better plots than these.
My suggestion is to avoid watching this sh8t .