I think the family plot will appear
Well, Gyeol did initially not believe Doyoon to be his senior and had a hard time accepting it when he thought it was all in his head. However, Gyeol regretted not holding onto his senior when he could, now that he is aware of the fact that Doyoon is his senior that he loved, him not being able to accept it would seen counteractive.
Doyoon did have a hard time to accept being in og Doyoon's body. He knows what the og Doyoon went through, how much he struggled and how lonely he was which only made him guiltier to take over his body. But he decided since he was the only one to know the truth apart from og Doyoon, he'll be the one who mourns og Doyoon truely and he made peace with that. But know that Doyoon still felt that he was the reason for og Doyoon's death until recently.
The family situation has already been showcased and kind of foreshadowed may be they'll elaborate in the future/next season.
The thing that made this story interesting was the soul switching but now that he knows everything it has become a the regular mundane cliche love story.
They could've kept it interesting if Gyeol had a hard time accepting Doyoon in his new body or Doyoon not accepting himself. Or maybe past Doyoon's family had secrets that the now Doyoon would uncover.
Anything would do.
I am over this nothing happens love Stories