I'd head up into the North Shore area if I were you. All you gotta do is hop on the H2 from Honolulu, which will take you to the 99, past the Dole Plantation, take a left to the 83 and that's where most of the good spots are. the island takes a bit under an hour to drive through the center if I remember right.
There's a lot of sweet hidden beaches the further north you go. Haleiwa area is pretty cool to hang out in. Waimea Bay is where Pukukea beach is, that's next to the Bonzai Pipeline so it might be tracked a bit. Kawela Bay is nice too. Those are all on 83. If you keep going around the northern sides of the island, it's pretty nice. Castle beach is further away but pretty sweet. Forest reserves, hikes, waterfalls.
If you go left and take the 82, there's a few small beaches but there's also an airfield over there so, I don't know how easy it'll be to get to the whole Mokulēia area. But there are a lot of cool forest reserves, Mokuleia, too.[img=]857431[/img]
North is good cus the locals have been fighting to keep overly kitschy tourism out. I only say you should go to enjoy it while you can and if you want a more pure experience, that's where to go. When we went, I remember talking to some of the locals about life in heavily trafficked tourist areas and just how much it sucks when people aren't kind in general. If you do go, obviously be respectful, enjoy nature kindly and whatnot nobody has to tell you but it's always good to spread good vibes...