Need Unusual Hawaii Ideas

[prtlndblnd]

We will be spending a week with family in mid-December on the big-island (or Maui, as family has not totally committed to a location) and then want to head off on our own for about 5 nights.

Looking for "off the beaten path" ideas (Time with family will be very tourist oriented events) Even recommended websites would be great.

So long as it is:
Reasonably easy to access from the big-island (or Maui)
Reasonable to take a hearty, very active 5yo along.
Has showers.
Not super expensive
Would prefer to be in a more secluded location.

We have not been to Hawaii as adults, so know very little.

Thanks!!!

Hawaii, here we come!