I've thought about changing the number of PAS settings but it would be to increase them from 9 if I could, or alter them. This is the reason: I like to pedal at a certain number of revolutions and a certain resistance. Very often on level ground, of the the PAS settings in the middle range, none of them match up with how I want to pedal in any of the gears. I still want them for when I'm accelerating and switching up PAS levels and gears same time. But I'd want an extra setting in there. I've used the very low PAS settings almost never. Usually I use the throttle and pedalling together to get going from a stop, letting off the throttle soon after, and using minimum PAS 3. No use going to a setting that you're already going faster than setting 1 or 2 would be useful for. Minimum from a start up is setting 3.
So the best thing would be either an extra setting or be able to adjust some settings. I have a 7 gear bike. I usually feel good with PAS 7 when riding in traffic but 8 feels better and 9 is great. I like to keep up to traffic in many situations in city. However, I also want to get the exercise and make the battery less stressed. So I could easily do without settings 1 and 2 because I use throttle starting up from every stop. I do not want to be without any of the higher settings.
If I rode in the mountains probably I'd have a different need.