About #3, wearable 4K:
“… and just still taking frames from the footage for newspapers and magazines rather than carrying a dedicated stills camera.”
Are you looking for the next “revolution” in photography?
I spend some time thinking about it, and I do not think it is going to be that easy. 4K in itself is not even the enabler. Lytro/etc tech allows to adjust focus. But that alone is not enough, though IMO would be a prerequisite. Adjustment of DOF and perspective at the moment are only possible with the stereo imaging. IOW, you need two cam setup shooting in parallel, using Lytro-like sensor, to allow for correction of: AF errors, DOF and perspective.
Started out doing photography at the age of 6 using an uncle's old 1940 kodak brownie box camera. At 15 years of age, I decided to buy my very own 1975 Praktica SLR camera. I now shoot with a Nikon D850. I do unpaid TFP and commercial paid work.