I'm going to take the advice here and ignore complaints that I don't agree with. Then maybe I can actually finish it.
That's pretty much how it's gotta go hehe. Thing is... odds are most people have SOMETHING they don't like about any particular thing. Just because they don't like a certain thing or suggest it should be changed doesn't mean that you should. It sounds like the OP is trying to describe the ending like a quick patch up for an out of control plot line (a la prison break)... but I really disagree with that. If you look back at the story, it makes sense. Even if you weren't given specific clues, you can look back at the fact that you start out looking just to wander around then you KILL A TON OF GODS. You can also look at Naija's internal darkness, such as when she swears revenge on whoever took Li. The fact is that Mia created the darkness within her, and all it took was some leading to build up her destructive potential.
Some criticism is valid, some is wrong, but... neither one means you have to listen to it =P