Okinawa is a weird place to me. Many places are very military market based and then there's the domestic tourism places.
Cool places:
Castle in Naha (can't remember name)
Ryukyuan classical music/dances performance at the Performance Arts Center (Can't remember the name of it either
)
As Dave said, Itoman (suicide cliffs area) has some nice topography for pics but better in the early morning.
Off Okinawa:
Ishigaki island
2 places I still remember are islands OFF ishigaki: one is the big island of irio-something: nice wildlife in the forests and landscape is cool.
The other place is Taketomi Island. Very pleasant island landscape with houses, like the Japanese Santorini. Not a lot to do but this is like old japan.
For the Cheng family activism:
Yomitan Fisherman Association: Go kick their asses for keeping whalesharks in nets for japanese divers.
Naha Aquarium: Boycott them for replacing their whalesharks from Yomitan.
Yonaguni:
Having dived there for a few days.... I'd rather go for the hammerheads than the monuments. It's not all that and more than a few scientists have stated it as natural. There are similar steps to those off sunset beach in Okinawa, but with overgrowth unlike the Yonaguni ones.