It was explained to me this way. If you reach into a black box with a fork, you will pull out ice cubes and if you reach into the black box with a spoon you will pull out water. The choice between a spoon or a fork determines what comes out of the black box.
However, the "observer problem" goes far beyond wave/particle duality.
Yes but the metaphor applies to all of the dualities. The wave/particle duality just happens to be one of the easier ones to illustrate. The observers choices and even the experiment itself determine in large part what type of results we will get.
You seem to be trying to go beyond the results of the experiments. As far as I know, that is unknown territory : ) If you know of a way to test the many worlds theory, or string theory, etc. that would be great. Better yet it would be nice to unify Relativity and QM that would answer a ton of questions.
I tend to agree with the emergent properties theories though and don't think we are going to unify everything. For example ice, water and vapor are the same molecule but they each have distinct characteristics depending on the phase change.