Hmm, it is interesting that that exists but it seems like it is cannot have been very serious because it dates from over 30 years ago and no followup activity happened.
How would one even start "serious design work on a self-replicating spacecraft"? It seems like the technologies that would require to even begin serious design do not exist yet.
That doesn't seem like the consensus view to me. It might be the consensus view among LessWrong contributors. But in the AI-related tech industry and in academia it seems like very few people think AI friendliness is an important problem, or that there is any effective way to research it.
Another problem you need to avoid is misjudging how much money you would actually save. That seems more common when the pain of misjudgment is shared.
It seems like picking this nonhuman metafictional stuff is a tough way to start writing. Maybe pick something easier just so that you succeed without getting so much writers' block.