I'd probably not go too far with themed food as it would get expensive and more complicated. And really, does anyone truly like Poi?
You could be successful with your decor and small touches.
Lots of colorful fruit, especially pineapple
Fruit kabobs
Use ham such as cubed for appetizers (along with cheese or fruit), pulled pork - which makes great sandwiches and is easy to keep warm in a crockpot, or other sandwich makings.
We planned on doing an Hawaiian Luau as our Staff Appreciation lunch, but my officers and I are wondering what type of food to serve. We usually serve food for 1 1/2 hours, so it has to be food that we can keep hot in a buffet server or cold on ice. Does anybody have any ideas of what kinds of food we could serve?