Okay, so far it's really good I see the potential on it, don't stop it! I've been looking for a game like this with this plot for a long time. I think it's going to be good if you add more 'choices' on what the player wants to do, like being a main singer or dancer, you know the k-pop roles themselves.
I don't know your programming skills but you could also put a skill set system like a menu or something that progresses with training (having a cheat system is also cool).
Romance option, I don't know how you want to proceed with it but having romance can be cool and dangerous. If you stick with the k-pop rules that could be even more interesting to see at the gameplay.
These two girls are really interesting, I hope the MC can debut with them. And I hope we can play as an Idol, maybe on part 2 of the game lol.
A thing that I did like to see is more dialog options to give more personality to the MC, being able to shape their image can make us immerse more in the lore.
That's it, I hope you don't give up on this project because I really love it. Well done!! Fighting!!!