I'd say yes even on Honolulu. The North shore of Oahu is beautiful and worth exploring and even Pearl Harbor is a bit of a pain to get to (or expensive if you take a tour...) w/o a car. Just my opinion.
BTW, using FFNs for a tour of the Hawaii Hyatts is like the holy grail, rivalled only by FFNs at the Park Tokyo or a Paris property. Congrats!