Help, Okinawa Holiday - not a visa run!

Hi I am going to Okinawa to stay with some relatives for a week or so in July. But I can’t find out anything about the place, except archives threads on visa runs. Can anyone give me a few suggestions about good things to do? Are the beaches nice? What’s the shopping like? Food - nice restaurants? Any culture to see? etc.
I can’t decide whether to go for just a couple of days or maybe stay for a week if it sounds interesting.

All suggestions are appreciated

Thanks a million!

Why not ask your relatives?

I will ask them when I see them. However they are distant relatives which I haven’t seen since we were children. I am trying to decide how long to spend with them in Okinawa without offending them.
If Okinawa is a sort of quiet place with not much to do, then 3 or 4 days may be long enough, whereas if it’s a beautiful/ interesting/ fun place etc, then I could spend a week there and make it more of a holiday.
So I’m looking for your advice before booking my flight and commiting myself.