[bigquestion]

To increase the efficiency of many people working in diverse domains, probably a '1-size-fits-all' solution would be hard to find. So something generic - one idea is, generally getting mentored by someone more experienced than you increases your efficiency/helps your career. (Mostly) everybody could use a guide/mentor, either for careers or personal lives. It could be a sort of referral program - to get access to a mentor older than you, you have to mentor someone younger than you.

[insoluble]

Certain healthcare innovations could in theory increase efficiency quite a bit for many people across various domains. Only if there were a way to make people smarter. Perhaps computer-brain interfaces could improve efficiency in some areas. Nevertheless, most improvements in efficiency from an innovation would be in a specific set of domains.