In some ways I think you’re looking for the wrong thing, or rather, using the story ending as the means for evaluating what you want creates an ambiguous question, at least in Dramatica terms.
As you know, you do not need to KNOW the ending for the storyform to tell you what the ending should be based on other parameters you DO KNOW about the story. So your question itself is too ambiguous per se. You might break your question into the following camps:
– I want a story where the end is ambiguous. This is then a matter of storyencoding and storyweaving, not a storyforming matter. I suggest you look at “The Lady and the Tiger” or the original short story, “The Birds.” They are a tales and thus unpredictable as to how they are supposed to turn out.
– I want a story where the meaning of the story is ambiguous.
– I want a story where the perspectives in the story are ambiguous.
– I want a story where the context of the story is ambiguous.
– I don’t know what I want except that it should be “different”.
Just some thoughts.