That is a great set-up.
What speed do you cruise at? Is the motor able to match pedaling speeds?
The battery would make a great ballast at the front. If you intend using it regularly solo you could run a lead inside the hull from front to back that terminates in waterproof through hull connectors. You could then just plug the battery and motor in. A framework for the battery that clicks into the front click n go wouldn't be too hard to make. Maybe piggy-backing off the drivewell plug?
That is a great idea using it as a ballast, and running cables trough the hull. I will probably do that eventually. I need to get a speedo for the mirage drive, or get a GPS like some of you have on this forum, so I can test speeds. On 5th speed (fastest speed) it is probably as fast or faster than me pedaling alone. Today, I was in 5th speed, using the pedals, and paddling all at the same time. I was really cruising!
I also gave it a good test today, I went about 3 miles against a very fast outgoing tide. Without the motor that is very exhausting, however with the motor, I stopped pedaling and was able to get rest breaks. Normally, if I stop pedaling against the current, I immediately stop and start going backwards.