The Kileaua Lighthouse has some interesting history and is nice to take pictures of.
The surrounding wildlife, mainly seabirds of many varieties, are interesting to view, observe and read about. Nice place to stroll about for a half-hour or so.
Parking is ample; it costs $5/pp to get in; note only open from 10AM-4PM.
Beware, there is no natural shade up there, it can get very hot, so plan accordingly.
I consider this site a one-time only attraction, would not return if back on island.