Responses
I think this series is suppose to be more of a "one volume per family member" kind of thing.
But I agree, no real story depth
Japan has a lot of "ansoros". It's written to be like an anthology on purpose, albeit with one continuing lineage.
Basically, just consider it to be a collection short stories, it's not meant to have depth, but just be a fun and easy read.
(Which I personally find enjoyable sometimes when I want a break from 80 chapters of drama that goes nowhere XD)
There is no depth to the characters, no character development, and the plot is moving so fast. It's like all the chapters are short recaps of some other story. It is kind of easy to read but I don't feel any attachment to the story as a whole.