The first ~half was dragged out almost to the point of tediousness. Actually considered dropping it. One thing that kept me going was the good depiction of Tau's thirst for revenge. I appreciate that while the protagonist's (or, if you prefer, anti-hero's) drive was completely built around revenge and hate, not once was it glorified. Instead, it was always portrayed as the dreary, unfulfilling thing it is.
The latter half of the book got better, but I still think the fact that the people Tau wanted to take revenge on for killing his father also happened to be the main villains of the story was a bit too 'convenient'. There is one person he wants to kill, and since there's no chance he would come out of the story as anything else than a monster if there was nothing more, that person also betrayed the queen. Tau is depicted as not giving a fck about helping the queen and only wanting to kill, so at least there was no face-heel turn.
I am still undecided how many stars I want to give it. Four ⭐⭐⭐⭐?
... nah, I guess I will go with three, because I was promised dragons and I didn't get enough of them. But I might read the next book in the series, eventually, which is not something I' expect, based on the first half of the book. Or - wait wait wait. Actually, four stars, because the world-building was decent (tight, even if not especially deep) and the characters were fine as well.