Therefore you agree that philosophy is important as the majority of these things cannot be done using any method that can be considered remotely scientific.
If you think philosophy should be thrown in the bin, then you think science can answer these questions, but it can't because it's not simply 'philosophy 2.0'.
All I can say is that I think you have a very narrow view of what science is, what science means.
Science is not merely test tubes, lab work, and rote data collection. Science is both quantitative and qualitative in its approach. Science is Philosophy, but practiced in a way that starts with the current scientific understanding of the world upon which to build understanding from, and makes a concerted effort to mitigate the shortcomings of the observer/philosopher.
I do not think Philosophy should be thrown in the bin, I simply think we must ensure that Philosophy is practiced in a way that meets current standards of best practices. That science and philosophy are not two separate endeavors, but rather, the same endeavor with the same simple goal, to answer general and fundamental questions.
The steps at the beginning of this process are meta-ethical, and so we can't simply say 'we will improve the process by using science' no matter how much we want to avoid human imperfection and fallibility.
Other than that myth should be ignored in the meta-ethical process and the variables associated with the meta-ethicist are factored into the process.
You have basically just described the contemporary approach in most of Western Europe, there is nothing new about it.
Which means that my concerns are being resolved and modern Philosophy is conforming to best practices. The schism between Philosophy and Science is resolving and both are again, coming under the same tent.
It is also can't be described as 'scientific ethics' as its foundations have nothing to do with science. This is scientism, an exaggerated belief in the scope and efficacy of the methods of science.
The only reason I see to claim there can be an exaggerated scope and efficacy to Science is to shield myth and raw intuition from the principles and standards of science. Really, it comes down to protecting the established bias of individuals. It is myth and individual bias that is threatened by science, and it is from these quarters that we hear the cry of scientism.
Ultimately, you have favoured the rights of the mother. For example, if the father, or family wanted to raise the child then it can't be described as unwanted. You mention the emotional impact on the mother, but not on the father or family. You mention a burden on the state, but not the negative impact of declining birth rates in an ageing society. Also that because some pregnancies result in miscarriage, then that is analogous to abortion, which is questionable at least. You have also defined life as starting when the foetus has developed to the stage that it can be 'self-sustaining' (and is this actually self-sustaining or can be saved by significant medical intervention?).
I'm not saying your view is wrong, or advocating the opposite, just noting the subjectivities involved in the process.
Certainly you will grant me some latitude and accept that this is a mere sketch to outline the point, certainly not a full treatment of the issue.
The goal was simply to show that myth would not factor into the process (at least not at the beginning) and to also express acknowledgement that we are still talking about people, warts and all, and there will have to be compromise in the end.
While you utilise scientific information in the decision making process (as we already do in practice, and as many moral philosophers have done for as long as we have had science), the principles you use to choose between options are not scientific. This is the fudge in claiming we can have scientific ethics.
For example, science can tell us when a foetus becomes a viable human, but it can't tell you if the point where it becomes a viable human is the point we ought give it the right to life. Even then do we give it the right to life, or do we allow late term abortions in certain situations? If so, what situations? What level of risk to the mother justifies termination after this point?
Ultimately, the answers to these questions are philosophical, not scientific.
Again, all I can say is without consensus between us on what is meant by science, you will continue to make distinctions where I see none.
These processes must be done, under whatever label we choose. What is important in these decisions is in what we allow to influence these decisions. Are we going to permit myths to influence these decisions? Are we going to let raw intuition influence these decisions? How often do we hear the phrase “counter-intuitive solution”, a solution that contradicts raw intuition and is yet the optimal solution.
To narrowly constrain the term Science only to what occurs on a lab bench is to not understand what Science is and why the schism occurred between Philosophy and Science. For the ancient Greeks there were no limits to the questions Philosophy could address, no boundaries of scope. The same holds true today for Science today. There is no boundary, there is no limitation of scope. Whatever label you chose, be it Philosophy, Science, Scientific Philosophy, or a new label, the modern approach to addressing and answering these general and fundamental questions is, essentially, Philosophy 2.0.