I understand your needs. But you're spending a lot of time and money trying to shoehorn a concept into reality when in fact the simplest solution is to get a beater beach TheMightyHobie18 (throw a spin on it for your kicks) and a racing F18 to take to regattas.

Regardless of the boat chassis, I wouldn't want to race a boat that was kept on the beach and subject to the treatment that you've described.

If people "jumped" or "partied" on my boat, the next day there would be a big "GTFO" sign on it somewhere, enforced by some caltrops.