Review: Throne of Glass by Sarah J. Maas

Throne of Glass Throne of Glass #1 Sarah J. Maas

After serving out a year of hard labor in the salt mines of Endovier for her crimes, 18-year-old assassin Celaena Sardothien is dragged before the Crown Prince. Prince Dorian offers her her freedom on one condition: she must act as his champion in a competition to find a new royal assassin. Her opponents are men-thieves and assassins and warriors from across the empire, each sponsored by a member of the king's council. If she beats her opponents in a series of eliminations, she'll serve the kingdom for three years and then be granted her freedom. 

Celaena finds her training sessions with the captain of the guard, Westfall, challenging and exhilirating. But she's bored stiff by court life. Things get a little more interesting when the prince starts to show interest in her... but it's the gruff Captain Westfall who seems to understand her best. 

Then one of the other contestants turns up dead... quickly followed by another. 

Can Celaena figure out who the killer is before she becomes a victim? As the young assassin investigates, her search leads her to discover a greater destiny than she could possibly have imagined.

I was curious about Throne of Glass. I haven't read any reviews before reading it but I've seen a lot of my fellow readers and bloggers give it 4-5 star ratings. 
Five chapters in and I was smiling. This is going to be good. I had a sort-of Poison Study/Girl of Fire and Thorns throwback. But as the story progressed I became less and less convinced. At the middle of it, I took back that comparison.
My frustrations mounted when the story arrived at the castle and the Champion competitions were underway when the characters were continually being exposed.
Celaena Sardothien was an assassin. Or she was supposed to be. She was too vain and arrogant to be an assassin. To me, an assassin is shrouded in mystery and in shadows, in cunning and manipulation. But she can have her faults and her quirks, this time her fondness for clothes and opulence. Celaena was not quite what I was expecting - in a bad way. One could argue that her sunny sarcasm along with her beauty could be a mask to hide her true being. The character she projected here did not effectively reflect what she had gone through, all those years as being an assassin. A talented hawk hides its talons they say but that adage is more appropriately conferred to the king of Adarlan and Duke Perrington. 
Who I admired more was Nehemia. She was somewhat a minor character here but I predict that she would play a larger role in the next book. Yet her character was what fascinated me more because with what little exposure she had here, was enough to convince me of her character.
There was the matter of the leading men. I was partial to Chaol from the start and, frankly, he's one of the major reasons I kept going. He had the stability of spirit and the strength of his convictions to make me believe that he would be good for Celaena in the long run. But we could see, based from his last major encounter that he also has a lot of growing up to do. In this regard, he has more in common with Hector from the Fire and Thorns trilogy.
Dorian on the other hand has a lot - a whole lot - of growing up to do. He has a good heart, a conscience but he lacks a spine. Trapped in his role as the crown prince, he is torn between this label and the right thing to do. His affection for Celaena was, to my eyes, a novelty for him. An escape. If ever, I ship him with Nehemia. She would be good for him. 
Aside from the tests to determine the king's champion, a murder mystery also drove the plot. The villain was obvious from the beginning despite throwing a curve ball that was supposed to confuse the MC and the reader. Nehemia, as the perpetrator, was the logical choice, true, because of her background and supposed motives (which were quite true but in a different way) but looking closely at it was not very convincing. Not true to her character. 
I still couldn't complete the picture that holds the Erilea together and the conflict that puts Celaena Sardothien in the middle of it. Hints of a past that's somehow significant to the fabric of that world are the key to this whole thing. 
Throne of Glass is good but I'm worried if its main character could carry the series and convince me of her worth as a character for this world.

P.S. Someone said to read the novellas as to delve further into her character and I would see what I've been missing.