I talked briefly with someone who did an organized Erie Canal tour. It sounded too tame for what I would want (I want more effort or higher miles than it sounded like they were doing).
Now I know this will sound weird but I've always wanted to do the actual canal on a boat that is bicycle powered. I figure two riding stations where bikes can be clicked into a propeller drive system; maybe a lightweight pontoon setup with a coverable deck area. Bikes can be extracted for some exploration of towns or local sights.