An Ending That's a Little Uncertain
I rate "open endings" on a scale of 1 to 10, with 10 being the most open. The Empire Strikes Back would be a 10, for it left us with a cliffhanger that demanded a sequel.
Of course, George Lucas knew he could get away with it for that particular film. Usually you don't want to make an ending that open, because it leaves a story feeling unfinished. Your player, who has worked so hard to reach the finale and who finds there's no "end" there, will usually feel cheated and manipulated.
On the other hand, the ending of Crouching Tiger Hidden Dragon, is about a 3 on that 1 to 10 scale. We know that when Jen jumps off the mountain, she's going to get a wish fulfilled, but what did she wish for?
This question emotionally engages us because each viewer will complete the story in his or her own mind, in his or her own way.
My belief is that, if Jen turns down her boyfriend's invitation to return with him to his home, which she does, it must be for a pretty important wish. I believe that she wished for Li to come back to life, and that all her other misdeeds will be undone as well.
Given that she has completed her Character Arc (she has learned ethics and responsibility), this would seem to be a logical motivation for her decision to make such a great sacrifice. (Because I think Li will come back to life, I don't even see his death as final. To me, the film had an uplifting ending, not a sorrowful one.)
Of course, I can't prove that that's what Jen wished for, and you might have a quite different and equally valid opinion. And that's exactly the point: The ending is a little open, but not so open that it frustrates us by providing us too little to base any speculations on.