Honestly? There is nothing to do....
We found Honolulu and Pearl Harbor (Wakiki, Diamond Head, Hanauma Bay, etc) to be dirty, crowded and the worst traffic I have ever seen. We spent the better part of two days doing the 'Must See' places, felt like we really wasted those days and wished had had just stayed at Aulani.
The North Shore was wonderful, I was awake by 4:00am anyway, so we drove up a couple of times to watch the sunrise and eat breakfast. Lots of great beaches, food, shopping.
I dont really enjoy the tours (helicopter, boat, horseback, etc) since I always leave thinking it wasn't worth the money. $100+ for a 1-2 hour tour seems kinda ridiculous. That being said, we didn't do anything like that, so if you like those things you might find more to do. We did buy a luau package from the tour desk at Aulani, but we only stayed for an hour and went back to the resort. From what we could tell the theme for the night was 'The Bar is Open'. Almost as though the whole point was to drink as much as possible...The staff at Aulani was great and they gave us a full refund and were able to get us a great sunset view table at AMA-AMA that same evening.
I think Aulani is by far the best DVC resort in terms of service and quality, nothing else really comes close. It feels like a luxury hotel. The staff is amazing, the pools are great, the swimming lagoon is a nice feature.
We will be back to Aulani soon (we have family in Japan, so it's a convenient half-way place), but I would say for my money....I would take a Florida vacation, just because of the flight time and expense. For what we spent just on airfare for my wife and I we could do a nice 10 day WDW or Hilton Head trip.