If I understand the thread correctly the problem is low turnout at regattas. Adding a jib to the F18ht will not solve the problem. Look at the F18, it is a healthy class with good racing and that's why they sail it, not because it has jib and weights 180 kg and can't use carbon masts.

I sail the Hobie 16 for several reasons, but the design and performance of the boat is not one of them! The boat is a challenge to sail well, not too expensive, good sailors in the class and they have excellent parties at the regattas, that's why I sail it.

/hakan