I started reading Leigh Bardugo's other series, the Shadow and Bone (Grisha) trilogy, but I just couldn't get invested in it. I've only finished the first book and started the second. I'm not sure I will ever finish it, not when the only really salvable thing is the villain. 
 Shadow and Bone was boring for me, plain and too short to have proper character or plot development for a non short story. HOWEVER, Six of Crows is a delightful surprise. 
 When was the last time you wanted to hear a life story about a person you just couldn't stand, no matter how interesting the story? Like if this someone you despise went traveling around the globe in 80 days, you wouldn't be interested in hearing it. In fact, it could be the opposite. It's the same principle for a novel, I think. One of the most important (if not THE most) thing of a story is the characters. If they're not interesting enough to tell and sell the story, make the reader care, then the story--no matter how great the world building and plot are--won't work. 
 In Six of Crows, the characters are layered delightfully, most of them morally ambiguous, with personalities, different talents and weaknesses. They read feasible, and not just that, but you care for them. (Despite some of them are not good people.) 
 The way all these kids were so damaged and yet able to feel and care, and the fact that none of them was stupid, was just gold. If they committed any mistakes was because they're humans (well, fictional humans). 
 Kaz ,the protagonist, was particularly intriguing; the kind of character that makes you question your morality just for not hating him. I adore smart protagonists like Kaz; the kind that always have a card hidden under their sleeve. In better circumstances I think Kaz could have been the sort of scientist or intellectual who would have changed the world for better, but in this story, he's a master criminal mind. 
 Inej was so strong, such an unbreakable spirit I just couldn't help but adore her. I liked the rest enough, and the dynamics between the gang were very fun to read. In fact, this book has some hilarious passages. And about the love... Well, I'm secretly a romantic, so I adore love (in any form) in books. But I hate when romantic love takes over the story, because that is not all in a person's life. That did not happen here though, and the love made every character better, stronger, care, more human, which is always a good sign. 
 The plot was as good as that of the best movie you can think about an impossible con or robbery, and that exhilarating, too. 
 As for the world-building I didn't feel Bardugo was as excellent as she was with the characterization or plot, but it was good enough. I think, though, that the explanation of the world was a bit confusing, the naming particularly. Sometimes I wasn't sure if the word referred to a place or a person, but I can easily forgive that because the rest of what constitutes the story is just that well written. 
 I think Bardugo's writing evolved spectacularly since Shadow and Bone series. Maybe it was related with the choice of PoV, but even having an omniscient narrating voice won't help if the writing downright lacks style and strength. 
 All I have left to say is that this book is definitely worth your time. So go check it out. It's not perfect, but almost.