Options. Design it with an inline electric motor like Ecospeed so it is ready for it but can be bought without it. Crash panels so that parts of the fairing can be easily replaced when damaged and not the whole fairing. The criticism of electric drive could be made for any electric assist bicycle and is not really valid. I use my electric when I am towing a 300 lb loaded trailer or need to go fast and far. I am currently installing electric on a bike for a nurse at our hospital so he doesn't get to work really sweaty (big hill). The battery storage area should be large enough for someone to add extra batteries and the box shouldn't be made to fit only one size of battery. As battery technology improves the owner could upgrade.
Cars seem to be reliable at first but if you read the owners manuals, you would fill up your tires regularly, it is just with a car you don't need the performance, you just need a heavier foot. An internal geared hub option would be good like the Rolhoff. Offer it in two or three wheel version. When it comes to lights, they are improving all the time. So some places to mount lights so they can be upgraded later.