I am a bit disappointed at the ending. But being set in such a dire historical time for China, perhaps it couldn't have had a different, more triumphant ending. I think Chong Yang is the core of the story. He IS China. He represents what the country went through and the values it chose to hold on to throughout the horrific episode of the Sino-Japanese war.
Other than that, I enjoyed the way the characters developed from weaker to strong and determined individuals, but it would have been nice to see more of an edge to them.