"(fully attentive) human drivers" probably cause deadly accidents every day, and they certainly behave in surprising/irritating ways. Anyways, a human driver going the speed limit is no hazard, so I fail to see how having self-driving cars follow the limits could be a problem.

Autonomous cars need to share the road with human drivers, so they should not behave in a way that is surprising to humans, to the extent possible.

Point of clarity: are all of your services rendered remotely? No need to move to a big city (until a job requires it, at least)?

Yup, everything is online.

"Private Placement Memorandum" - first result on googling 'investor PPM'

From a legal perspective, how would going more than 25 MPH be relevant?

Higher speeds are more dangerous, and thus require more safety equipment.

Helmets go on top of your head, they shouldn't limit visibility. The practicality, and point, would be protecting you in the event of a collision.

When travelling at 100km with no seatbelt (legal in many areas), in a collision, you become exposed rather suddenly.