What are your rules about bicycles? In Sweden, we regulated them kinda like bicycles - as long as the motor has an effect under 250w, and is limited to driving at speeds of 20km/hr, you’re able to use them in the same places and manners as other bicycles.
Recently they started to require traffic insurance, and basically all insurance plans have zero deductibles as long as you’re wearing a helmet. I barely see anyone with helmets still, but yeah…
Or is the biggest nightmare that there’s not many designated bicycle paths, and so people are zooming around where pedestrians are walking?