is availability of surplus amps for recharge, and taking it back to the boat nightly is a PITA. Same issue of recharge with the Torqueedo outboards.

Also the Torqueedo and this bike look to me like high-risk theft targets, as they're just too cool (and portable, high-value). Even if you could lock them well enough you might need to take the batteries with you, the way people take quick-release bike wheels with them when they lock a bike in a place like NYC. The batteries themselves would be easily removed and they're expensive.