G'day Beersy,
I went over 2 years ago in July. Spent most of my time in Kauai, very relaxed place frendly people etc. Heaps to see and do. I didn't take my kite when I went though

but I watched a few guys kiting. They were all on 7m.
My sugestion would be to do a helicopter flight around the island when you first get there and then you will be able to sus some cool spots. I went with Blue Hawaiian Helicopters, you get a DVD etc so you can look back on it.
Also suggest to go on the Kalalau Trail to Hanakapi'ai Beach. Cool spot but its a fair hike.
PM me if you need anymore info.
Cheers