I have thought that extremely accessible, portable, non-radiation imaging would be revolutionary. Imagine every doctor - or even every person - had a handheld thing they could wave over your affected area to get a high res 3d image of the issue. Of course we have mri, xray, and ultrasound, but those are big and expensive. Obviously there are engineering reasons that is the case, but It seems like a concerted effort to make imaging more portable and accessible, coupled with ai to help analyze could bring about all sorts of follow-on health improvements. Your regular practitioner could check you for heart blockages, clots that lead to stroke, cancers etc as a matter of course. I’m not sure stepping into a golden vat of water is what I have in mind but medical imaging does seem like a possible area for drastic innovation.