There's one thing I can see working. Each pontoon fender has a part line with the flamboyant rocker panel. If it consisted of a cycle fender and a rigid mount with a pliable but rigid fill panel some limited wheel travel/steering could be absorbed by the fender.
Ross Lovegrove would be the guy to design it.
http://www.dezeen.com/2015/04/14/ross-lovegrove-design-schools-way-behind-need-embrace-digital-milan-2015/
I was looking for a picture of the underside on a chair seat that he did, this will have to do.