Let me precede this by saying I liked this show; it was fun to watch, and I've quite enjoyed it. It was entertaining, but not the masterpiece some opinions made me believe it would be.
I do appreciate the effort and work put into this, especially considering it was a passion project of War and Yin, and for that they really deserve a lot of praise. 
They both delivered amazing performances, but the show lacked properly built intimacy between their characters. For the record, by intimacy I don't mean NC scenes. The script spent so little time on building the foundation for their relationship that it just didn't work as a love story. In all honesty there was less screen time allocated for them being together and communicating than some unnecessary although fun thievery.
I really appreciate the accurate portrayal of people living in or near poverty levels. Most dramas show us beggars in designer clothes, living in spacious homes or apartments and driving new Toyota. The show portrayed economic struggle and social issues, lack of opportunities, education, and the necessity of going into debt really well. Thanks to this, the motivations of the characters entangled with these problems were easy to understand.
That being said, the plot, though interesting, was very uneven quality-wise. After a relatively long period of establishing the environment, there was a lot crammed all at once into the second half of the show. As a result, the pacing was all over the place.
I'm not one to nitpick on the "realism" of action shows, but some choices in this script just didn't make any sense. The prime example being the whole "ring of power" premise for the Four Horsemen. 
I try not to take things too seriously if the show itself doesn't, but these last 2 episodes? They've lost the plot completely. Playing a game of Monopoly to decide the level of influence? The collars? What in the squid game is this? The big bad boss ended up being a very one-dimensional villain considering how much time was allocated for establishing his presence.
It was simultaneously too much and not enough to make this show great for me. I would call this the case of putting form over substance or maybe a show that fell victim to its own ambition.