I imagine autonomous bicycles using gyroscopes to stay stable, highly integrated camera's with environment comprehension (Waymo off-the-shelf chips) to redistribute them over the city at night.

I love the vision of a fleet of riderless bikes taking themselves to where the system anticipates their need for the next day.

However, I also suspect that there will be a lot of car/automated-bicycle accidents since bicycle visibility at night isn't particularly high, and relies a lot on the rider's choice of visible clothing.

That's seems the easiest to solve, just put lights on the bike. There are already many products for this, some of them very visible.

Drone rickshaw might actually be a nice, useful summertime ride.