You absolutely do not want an overvolted anything in the front fork of a bicycle. It will destroy it, even with a torque arm. Anyway, overvolting isn't necessary in 2020 and Class 3 operation. Just get a system rated for legal levels of power. 750W in a mid-drive or geared (rear) hub will get you going as fast as anyone needs to go. Besides, if you give the wife the Verve and build yourself a rocketship the "she can't keep up" issue gets repeated all over again.