Hi Stewart,
Members of my sailing club in WPB, Fla. built Paper Tigers 20 years ago. They are an ecxellent design and very fast for their size.
The problem here in the US is that home built boats and kit boats went out of style 20 years ago. People don't do that anymore. It takes too long.
What sailors immediately began talking about here in the US on this forum was older production boats, close to 14ft long with new and larger and hopefully faster sail plans. That is one way to go. Another route is a paraller road to the F16HP class and F18HT class etc. I think a choice is facing the group. The lower the price of the boat, the faster and larger the class will grow. If you have to build your own boat to be competitive, the class will grow much more slowly in the US.
Bill