I recently finished the book myself, and it was a great read. I think that the first part confirmed what I, and most everybody, assumed, which is that we would like Celene and Brie, and dislike Gaspard. However the rest of the book slowly turned that upside down, as we learned more about the characters. Celene was absolutely ruthless in that she would say or do anything to maintain power, she seemed to love power above all else. The incident where she killed all those elves was a good example. She sent Brie to take care of the rebellion, which Brie did with the skill you'd expect from her, but in the meantime she learned that Gaspard was gaining favor by making Celene appear to favor the elves too strongly. So she decided the best way to show the nobles that she wasn't overly friendly with the elves was to murder a few thousand of them. That move both showed how evil she could be, as well as how foolish, because her move was so predictable to Gaspard that he was able to lay a successful ambush for her, an ambush that Brie saw coming a mile away, and would've easily prevented if she'd been with Celene instead of being held prisoner. That one part of the book showed well just what kind of leader Celene 'would' have been without Brie. She would've been much less friendly to the elves, and she also would've been easily outmaneuvered and lost the throne to Gaspard. Truly it was Brie more than Celene was the master of the game.
Of course for all of Brie's strengths, she in the end dissolved into becoming the worst of them all, when she came to believe (wrongly, one would have to assume) that Celene's actions in the battle against the varterral meant that she never loved Brie, that she loved Michel and was only using Brie all along, that she was merely Celene's 'tool', as she put it. There was no explanation given for Celene's actions during the battle, but at the same time we know that she loved Brie and didn't love Michel, so we're left without a reason why she did what she did, and certainly Brie can't be faulted for coming to that mistaken conclusion since she doesn't know what we know, only what she saw for herself. However her response was not simply to retaliate against Celene, which again would've at least been understandable, but rather to set about to prolong a war that would result in far more innocent people dying than even Celene had caused in her slaughter of the elves earlier in the book. A woman scorned, she became the worst version of herself, killing humans for power just as Celene had done with the elves. Indeed they were two of a kind in their own unique way.
Gaspard, for all his faults from early in the book (primarily his desire to go to war with Ferelden) , became the best of the three in the end. He behaved with honor, saved everyone's lives, and proved that he would indeed have been the best choice to lead Orlais as a man of character and ability. While of course my top priority, in my first playthrough, will be to reunite Celene and Briala regardless of who I have to put on the throne to make that happen, I tend to think that, rather unexpectedly, I would probably side with Gaspard if it were purely on the merits, something I never planned to do before reading the book. Of course when it comes to honor and character one should also mention Michel. Honoring his word when it meant losing everything, as Gaspard himself said, Michel was the very model of a chevalier. I don't really understand why Celene wouldn't take him back, knowing why he did what he did, unless the concept of honor is so completely foreign to her that she literally can't understand why he did what he did. As he is a powerful ally, she should be more than willing to return him to his place as her guard, she certainly won't find anyone nearly as valuable to replace him. The man who bested Gaspard himself, and ended his fighting career, who wouldn't want to join Celene's cause with such a fellow as her right hand man? Just as a recruiting tool alone he would be invaluable. But somehow he's not wanted, so he's left to wander around until, presumably, we find him at some point in DAI and help him kill Imshael.
Of course the big question at the end, who was the mysterious individual who killed Felassan. It would seem that Felassan's job was to get the eluvians, but instead he let Brie keep them. The whole 'why not let the girl try?' line suggests that the mysterious individual's goals are at least similar to Brie's. Could this person be one of the ancient, sleeping elves, who wants to wake up and retake the world for the elves? Seems like a possibility. And of course cutting off his final sentence before we even know who he was going to compare Brie to is frustrating. Was he going to say 'you'? Was he going to say 'andraste'? Was he going to say 'flemeth'? Or something else entirely? Rather a frustrating way for a book to end, not just on a question, but a question within a question.
In the final line, about Brie looking for 'her people', in truth the elves aren't her people, her people are the nobles of Orlais, because she was the true master of the Game, she lived it, she loved it, she consistently outplayed everyone, and were it not for her jealousy and mistaken doubting of Celene's feelings for her, she'd be in Orlais with her now, enjoying whatever new Title Celene gave her, the elves would've been much better off for whatever new reforms she'd have maneuvered Celene into making, and no doubt in time she'd have become Queen, or co-Queen, herself. So try as she might, Briala will never find 'her people' in the Dales or any of the other poor, elven areas of Orlais. Imagining that some group of people is 'your people' simply because you share the same race is as much madness in the world of DA as it is in our own world. She will find her people when, and only when, she returns to Val Royeaux.
The book was a fascinating and awesome read. While I wish that some of the characters (particularly Celene and Brie) had ended up being better people, I was certainly pleased that there were certain characters who exceeded my expectations of them (Gaspard and Michel) and of course the other characters were interesting also. If you haven't read it yet you owe it to yourself to do so, and having read all the major DA books (not the comics but the books) I can say that this book is the best of the lot, and certainly it's a must-read for everyone who plans to play DAI, as it sets the stage for the game very awesomely. Two thumbs up for this fantastic book!