But I do think they need to be at least as heavily regulated as ebikes - max motor power and speed should be in line with EAPC
Yes, because whether or not they are properly limited to 15mph, they are basically electric motorbikes. It nonetheless seems faintly ridiculous that an e-bike rider going at 15mph doesn't require motorcycle-level safety equipment, yet an e-scooter rider does.
I had the idea once that in order to prevent twist-and-go riding, the scooter should have foot sensors to cut off power if both feet are onboard whilst moving at more than, say, walking pace; and should only assist when physically scooting with one foot on. Of course that assumes wrongly that the only eligible users of an e-scooter would be people with two working legs.