As has been said, Fiji has a number of places to hide during Hurricane
season, so that shouldn't limit you (I grew up in Suva and the occasional jaunt moving our boat into the mangroves was not uncommon). My family are now based in Nadi and the boat that I sail on when home has survived unscathed for the last 6 years, so odds are, you'll be fine too.
The main thing you might like to think about though, is that the Hurricane/Cyclone Season is also when it is uncomfortably hot. Not HOT like here in the Middle East where I now work, but hot as in Humid, Sticky and Not Much Wind
. A number of years ago, I took some time off and went home to sit on the beach and do some windsurfing. We had one Hurricane
in the whole time I was there (December to May) and the Trades didn't really kick in until late April. It sucked!
April through October will be the most pleasant time. Although it is also "Tourist" season too.
On the Nadi side, Port Denarau (Port Denarau Online
) and Vuda Point (Vuda Point Marina Fiji - Yacht Haven
) are pretty small scale Marina's, but both have a bunch of boats for sale
throughout the year, so you may like to buy out there, sail (and cruise
, etc...) then sell when you've had enough. A lot of the boats we saw up for sale
when we were home in August, were well set up cruisers where the sellers had just had enough and were happy to quit. Can't remember what the lot at Port Denarau were called, but anyone of the Philp family (the folk behind The Yacht Shop The Yacht Shop - Fiji
should be able to help).