Although, this series was not really one of my favourite, the ending was beautiful. Adelina is not a great character, I don't particularly like her, but I don't dislike her either. I just do not really care. However, her development was really well done, we can see a lot of changes in her.
The plot was not that interesting, not that it was bad, but I just could not feel invested. I did not really care what was happening and I could not connect with any of the characters.
But the ending really did something for me. That is why I rated it 4/5 stars! Not a bad series, but not one of the greatest.
(The Legend series by Marie Lu was awesome, just wanted to mention that, I case you wanted to give it a try).