The Alakai Swamp Trail to Kilohana is a good alternative to the inaccessible peaks. Views over Wainiha Valley (really a mini-canyon) to Hanalei Bay are fantastic on a clear day. Was lucky enough to catch one.
I've hiked up Sleeping Giant three times, also Pu'u Pihea - two very fun and scenic hikes.
I was hiking with my step-sister in Waimea Canyon. She was wearing sandals and cut her foot badly. I had to carry her on my back, part way up out of the canyon.