1.)What parameters do you think are important to take into consideration when starting this process? IE building an e-bike to suit our personal preferences
The Primary parameter is your intentions. "whatcha guna do wit it?"
If you live in tebet, and you're going to be replacing your Yak to go up the mountians, Or in the tropics, and using it to haul virgins up the valcano to appease the gods, your needs are going to diffrent than if you live in, well, say.. Kansas.
2.)How would you (go about, approach) prioritizing these parameters?
Well, first of all, check your shoe. if there's no Yak dung on the sole, you're probably not going to need a bike that can replace a yak.
Now check around your village for a stockpile of virgins. If you find some, let me know, but if you don't happen to see any, and the volcano gods haven't erupted for it, then you probably won't need to be hauling anything up a volcano either.
So you can rule out the slow but powerfull torque happy Mountian and volcano climbing motors.
Now look around you. Do you see anything? anything at all? You do? then you're not in Kansas. Had you been in kansas, you would have needed the fastest posable motor, for getting the hell out of Kansas, but if you live anywhere between the volcanos and kansas, you'll probably need a motor that falls in the mid range of power and speed.