The issue is available torque, and traction.
The scooter tire is basically a slick (it was free).I have about 140 lbs of down force on the wheel. If I am on sand or gravel, the e-wheel is like a great pitching machine for stones,
so I tend not to use it if someone is behind me.
On my 42 mile test run, I did not run the gas engine except for an occasional 10-30 seconds to replenish the power brake vacuum. (need a small vac pump).
Acceleration on flat or down sloping starts was reasonable, and probably a bit faster than your 36 seconds, but it was painfully slow, and waste lots of amps to try and accelerate up a grade from a stop. If the drive had a 2-3 speed tranny it would probably have no problems, but my fixed 4:1 and my heavy Insight (extra 400 lbs of batteries and e-wheel), are just a bit much for the little e-tek.
Once moving, with the low rolling resistance tires, pumped up to 45 PSI, I was very impressed with the e-wheels ability to climb hills. A hill that I would have had to downshift to climb with the gas engine only dropped my speed from 30MPH to 24MPH.
If they come up with a higher power Nuvinc drive:
http://www.fallbrooktech.com/NuVinci.asp
I would consider using one in the e-wheel.
I just acquired a Honda Insight IMA motor, which may find it self replacing the e-tek sometime later this year.
http://www.99mpg.com/workshops/mikessaturdayhybri/
Too many projects not enough time or money.