Hi,
I'd recommend hiring a plane from a local flying club; I've done this a number of times on Hawai'i, Maui and Kauai - all have been incredible experiences with breathtaking scenery.
Of course you'd have to go for a checkout first, but if you don't want to be too hands-on, I'd suggest just renting the plane with an instructor - they've got the local knowledge and usually quite happy to give you a tour of the sites...inter-island flights are pretty cool too (watch out for the weather!) you can as much or as little flying as you'd like.
You could even take passengers if you rented a big enough airplane - I took my folks! PM me if you'd like any recommendations.
Enjoy!