The Silverblood Promise

The first book in a really long time I DNF'ed in pure frustration. I really tried, I did!
I read to 60% of the book and I really wanted to like this book, so I kept on reading, waiting for the plot to thicken, for the characters to develop, but... neither ever happened!
I dislike this book because:
1. the main character: he's just so incredible simple and often straight up stupid. That he has this ‘banter' that other readers refer to with this 10yr old little kid, only shows his immaturity. I don't know whyyyy the characters he meet on his way helps him or continue to place trust in him to do important tasks for him, ‘cause he keeps completely fucking things up with his complete incapability to figure things out. He goes directly into traps, even when the 10 year old kid says “this feels like a trap”, and then gets people killed, and then theres NO FURTHER CONSEQUENCE! Which leads me to my next point of criticism;
2. Is this supposed to be a gritty and cutthroat world? I can think of so many worlds in other books, where if Lukan walked into their city and tried what he's trying here, he'd be stabbed 5 times, and thrown in the gutter on page 12. He has no sense for survival, and yet keeps on surviving on pure dumb luck.
3. The plot is fast paced, I will give you that, but that's only because it is so simplistic. The thing about there being no consequences for his fuck-ups is a perfect example of one of a million loose ends. There's so many points in this story, where the plot could (and should?!) spread out and become more complicated, but just doesn't. It is very ‘then-this-happened-and-then-this-happened-and-so-on'...
I was also completely thrown off by the whole starting point of the story: the ‘silverblood promise'. It's supposed to be a goldblood promise, but because he has no gold, he have to make do with silver - ...whaaat?? We never get any real explanation of the meaning of this kind of promise, that supposedly means a lot, but then again, he makes it to his family's servant? To find out why his dad got murdered? They are in perfect agreement that it is important to figure our why and who did it, so why is this fancy promise necessary? Shouldn't it be perfectly clear when the whole book got the name from this scene? Shouldn't it be a focal point in the story? It didn't feel like it; 60% into the book, it never got mentioned again.
4. There's way to much telling and not nearly enough showing. I got the feeling more times to count, that the author didn't trust me to read the characters and situations right, and therefor directly told me how he would like me to perceive things. He did that a lot through Lukan's inner monologue, which felt odd; who describes people and their surrounding aloud inside their head?

I've never seen Indiana Jones, so I can't comment on the comparisons to that, but what I can say is that the comparisons to The Lies of Locke Lamora is waaaaaaay of. Lukan is FAR to stupid to keep up with the gentlemen bastards, the city of Saphrona has nothing on Camorr as a setting, the complexity of the plot is an ant to an elephant, and then there's the complete lack of interesting characters and engaging dialogue.

I cannot fathom how this book has 4 stars on Goodreads.
I spent £20 on this book and I want them back!