Thanks Jonah,
We looked at front motor and hub gears but we don't think they are safe in the wet and are certainly not good in ice or snow esp. with an 18" wheel, the torque will induce a spin and loss of traction. As yet there isn't a light weight centre motor that would do the job.
A double chain wheel is certainly a good idea. Thanks for the tip.
We too think that hydraulic disc brakes are important for commuters, of course mudguards, and rack will be available. The rack is made using the same tube as the cross bar, so a second battery can be carried.
All the best, David