For example do you think there is negligible chance that genetic engineering or pharmaceuticals could significantly improve human intelligence before machine intelligence gets very far off the ground?
Germ-line genetic engineering is almost totally impotent - since it is too slow. Gene therapy is potentially faster - but faces considerably more technical challenges. It is also irrelevant, I figure.
Pharmaceuticals might increase alertness or stamina, but their effects on productivity seem likely to be relatively minor. People have been waiting for a pharmaceutical revolution since the 1960s. We already have many of the most important drugs, it is mostly a case of figuring out how best to intelligently deploy them.
The main player on the intelligence augmentation front that doesn't involve machines very much is education - where there is lots of potential. Again, this is not really competition for machine intelligence. We have education now. It would make little sense to ask if it will be "first".
Suppose we could look into the future of our Everett branch and pick out those sub-branches in which humanity and/or human/moral values have survived past the Singularity in some form. What would we see if we then went backwards in time and look at how that happened? Here's an attempt to answer that question, or in other words to enumerate the not completely disastrous Singularity scenarios that seem to have non-negligible probability. Note that the question I'm asking here is distinct from "In what direction should we try to nudge the future?" (which I think logically ought to come second).
Sorry if this is too cryptic or compressed. I'm writing this mostly for my own future reference, but perhaps it could be expanded more if there is interest. And of course I'd welcome any scenarios that may be missing from this list.