RATING: Would not keep reading.
You're suffering from non-engaging writing. Let's look:
Deep within the bowels of the Middle District, the blossoming mercantile neighborhood of the city, lays an ancient set of tunnels, once the streets of a bustling ancient civilization, repurposed to serve as the sewer system of the current city.
So many commas. 7 words then stop, 7 words then stop, 6 stop, 8 stop, 11. And I want to be clear as this is paragraph three, this is your entire work up till this point. It feels like tiny little snippets of ideas. You have no flow or readability. Quick edit:
Deep within the bowels of the Middle District, the blossoming mercantile neighborhood of the city, lays an ancient set of tunnels, streets of a bustling ancient civilization repurposed to serve as the sewer system of the current city.
Large hexagonal tunnels of brick and mortar extend under the street, given shape by architects and arcanists, creating a network of hallways and large cisterns all over the underside of the city.
All of your work is establishing idea then qualifying it in a passive manner. Let's rewrite this paragraph.
Architects and arcansists shaped the large hexagonoal tunnels to [Insert Purpose/ Other intereesting fact that deepens the world building]. The rest of the information you provide there can be stricken with absolutely no loss of information.
Rating: Would not Keep reading.
You manage to engage the reader at the minimum level while also havign some extremely stilted prose and dialogue. It's an interesting combination to dissect. I actually had it more middle of the road until I rolled my sleeves up and looked at the writing.
You get shifty with the time frames, swapping between past and present.
There's a lot of repeateded phrasing that stands out: "On the other hand", "poker face".
Some nonsensical phrasing: "The general glaring and getting as close to stares in his eyes."
OVERALL
It's better than it has any right to be, in that you put the resources in the write places for it to function as a story the audience can read, but there are a swath of problems here.