I'd rate it about a B. Competent action story, but it lacks the great characterization necessary to go to the next level.
In particular, Daniel Craig's character is really underwritten. The script doesn't do a very good job of putting us inside his head. He's great in a fight, though. Also, Daniel Craig doesn't have much luck with the ladies for an action star - his Bond averages a measly one shag per movie, and here not one but both of his love interests die on him, having achieved nothing more than first base with the latter.
Harrison Ford did better; this is one of his more memorable parts in a while. He had the most affecting scene in the movie, the death of Adam Beach's character. But the resolution with his blood son just rings false; Percy was a feckless idiot at the start of the movie (though fun to watch Daniel Craig beat up and maim), and there's no story space indicating that's changed.
Olivia Wilde being an alien makes her casting a bit less odd, because early on I was thinking that she doesn't fit very well into the period compared to everyone else. She was deliberately impassive for the most part, but I liked that Ella was her own character and arguably was the real hero in the end, rather than just a love interest.
Oh hai, Faux Aang!
I was surprised at first when it looked like they had killed the dog, but then he turned up.
And last but not least, Clancy Brown as a good guy! A preacher, even. That's not something you see every day.