If it's a boat for kids it needs to look like a boat for kids. There is a reason why things look like they're made for kids when, in fact, they are. An opti doesn't exactly look like a modern high performance speedster.

This is, of course, if you aren't expecting to market the boat to adults unless you expect to first sell to the adult in order to get them to build it for the kid, and then you've created the same circle we're in now.