The story started great and had so much potential. It was fun, entertaining, gripping in the beginning. The story developed also quite well however, the last three/four episodes were major disappointment.
Park Bok ja was too great of a character to be killed off like that. In fact, in front of her even Woo Ah jin looked weak. Her story could have been developed so much more but instead of giving her a good suitable redemption arc, they just killed her off.
Her ending couldn't even justify her character.
Woo Ah jin character just got everything way too easy. It looked like the only hardship she faced in her life was her husband's cheating. She could have played an important, critical role in the problem her family was facing but the writer just took the "I am not divorced so I don't have to deal with your problem even though I brought the problem in the first place" approach.

Rest all of the characters were practically useless, especially the three siblings. They could have easily done this show without introducing Oh Na Ra's character.

In terms of plotholes, I feel the writer did not go into depth with Oh Poong sook's and that CEO's role. It's like they played such a huge role in destabilizing the whole family, yet their stories were left kinda incomplete.
Overall I had such high expectations from the drama but was absolutely let down by the last three/four episodes.