Sorry to hear about your accident and injuries. When it comes to two-wheeled transportation, it doesn't take any speed at all for serious problems to happen. I broke an ankle a few years back while trying to pop a wheelie on my kids' Razor scooter (yeah, stupid, I know
). I was barely moving, the front end popped up much more easily than I expected, and before I knew what was happening I was on my butt with my right foot underneath, in a very unnatural position. 3 days in the hospital, surgery, 3 weeks off work, crutches for a couple of months, another surgery to remove the plates & screws 9 months later... It was a good year before I could walk & run without a limp. I learned, as did you in your accident, that low speed agility is big, and thinking through what will happen with the weight you're carrying if a fall does occur is an important safety consideration. In your case, it was the battery weight; in mine, it was my rear end!
It's too bad that people don't consider bikes (whether motorized or not) to be more akin to motor vehicles than pedestrians. Too often I see people doing things on bikes that can only be described as stupid risks. Not long ago a high school kid here was killed on a bike because he was riding along a busy street (downhill) on the sidewalk going against the traffic. A car pulled up on a side street to turn onto that street, directly into the path of the bike; the kid's head hit the windshield, and now he's gone. No helmet, riding at dusk with no lights, no heed to the flow of traffic nor the rules of the road as they pertain to motor vehicles. Totally avoidable death.
I see people riding bikes on sidewalks all the time, most often on the opposite side they should be on. I think it's a behavior that people picked up from some rule for pedestrians when walking on a road with no sidewalk; walking against the traffic allows you to see an approaching car and move out of the way if he doesn't see you. But on a bike, especially a motorized bike, moving with the traffic is much safer than against it. I'm glad that there are regulatory exceptions for motorized bikes, but it's important on the sales end to educate users as to some of the safety issues involved with them.