When you imagine a fair coin being flipped and describing that with a probabilistic mathematical model, you can always imagine a classical story of what actually occurred. How you went from a spread out of possibilities to witnessing a single definite outcome. So I can understand the ontology because there is a classical ontology.
What QM is forcing us to do is write down as much classical story as possible, THEN SOMETHING TRULY RANDOM OCCURS. I can't imagine in my head any possible classical story. Both the coin and quantum "measurement" use probability theory in a similar way, but this is an important distinction.
When you say develop a new ontology, I really think you mean develop a recipe. I see no way to even comprehend anything but classical ontologies. I'm not sure if it's a limit of our, biology, imagination, or intuition. There is no classical ontology, nor settled ontology for that matter to describe the "measurement" of superpositions process.