40lb thrust marine version MinnKota. Can hit 4mph plus at full power, but feels smoother and quieter at 3mph.
Our little Old Town canoe is just 13' 3", but a longer canoe would prob'ly push just as fast.
Always bring an extra battery (see pic)for peace of mind.
...and yepper, here in Texas too ya gotta have licence, registration, and all the bells and whistles. Hence....
Note battery powered running lights, gotta have a horn and life vests on board too.
Birdwatcher