Nacra already has a F16 compliant boat. Not optimized for the rule, but fairly close in all regards but the (dare I say it?) weight. To be exact, almost compliant as the jib is 3.71m2 whereas the box rule calls for 3.7m2, but that's close enough for me.

It's called the Nacra 500 sport. And it's a fairly good boat. There is one at our club and I actually like the simplicity of it....