I really liked the original Selection trilogy. However, this spin-off series of America and Maxon's daughter feels very cliche in general. Eadlyn's personality is just too bratty and bland. Half of Eadlyn's thoughts in this book is about how she does not want to fall in love and how she complains about "tough" her job as the heir of Illea is. Erik and Eadlyn's relationship is more on the friendly side, never romantic until the last few chapters of the Crown. The end of this book feels extremely rushed, and Eadlyn and Erik's love story is quite generic and simple. There was not much character development in the book whatsoever.
Also, Eadlyn is HORRIBLE to Kile. There were so many romantic interactions between them throughout The Heir and a most of The Crown, and then suddenly, Eadlyn banishes Kile, sends him away from the palace, and falls in love with Erik instead?! After getting banished by Eadlyn for a year and returning, Kile apparently marries this random woman named Alice, according to the Happily Ever After novella. Alice never shows up in the books. There is no info and backstory on who she is, and no backstory for how she and Kile fall in love. The book just states that Kile is married to a woman named Alice.
Kile's bratty sister, Josie, is also married to Eadlyn's little brother, Kaden Schreave, without context or reason. There is little to no interaction between Kaden and Josie, similar to Kile and Alice. Josie is basically a less calculating, more boy-crazy Eadlyn and a generic "wannabe popular girl". Talk about a lack of variating personalities and backstories.
America's fiery, energetic personality is completely taken out of her character and she becomes this gentle robot who says the most unoriginal motherly sentences. Maxon is also really plain and has a lack of personality in this book.
Summarizing this book, I'd say it was okay, but it was extremely cliche, plain, had a lack of personality, mediocre plot, and a few rushed scenes.