The vellum slipper would be perfect; I'm sure you can figure out how to make the STDs.
Did anyone mention to you about the Sea Breeze point location at the Polynesian for a beach ceremony? I know that I have read people with smaller wedding parties have even went to the luau "Spirit of Aloha" show. I'm sure if you have a larger group Disney could do a luau themed reception for you too.
We're going to Hawaii for a week when we leave Disney a few days after the wedding and I'm so excited because of how beautiful it is supposed to be there.