This book, unlike many works published afterwards, wasn't superfluous for me. It was suspenseful, and though the end wasn't completely unpredictable, it was still blood curling and well written. I loved how you get an insight in Snow's mind and see how he becomes the monster we know. 
All the references to the Hunger Games trilogy are perfect, even if you don't need to have read it in order to understand the book. I definitely recommend !