GraceKrispy, I am so very jealous of you! You live in a state surrounded by by fascinating sites. You just can't go wrong. I haven't been to Hawaii since 1999, so I'm way overdue for another trip.
I was in Kauai the last time, in Poipu. I am terribly afraid of heights but I went to Waimea Canyon anyway. It was so huge and beautiful, it was unreal and didn't freak me out the way I expected. Maybe I *can* take on the Grand Canyon.