Trip to Hawaii

First time heading to Hawaii next month with the better half. I was just wondering are there anything we should see/do that aren't in all the glossy travel brochures/websites. Any advice, tips or help appreciated. We will be on Oahu for 6-7 days then cruise boat around the other islands.
We were planning to stay away from day tours preferring to go at our own pace, so we will be hiring a car when needed (at least that's the plan so far). It's kind of a celebration trip, hers for acing her nursing degree at age 40ish(and picking up a job in paradise) and me for clearing 5 years remission from leukemia.

Thanks for reading. Like i said any tips will be appreciated.

Where are you staying? I think Oahu is the most versatile place for a holiday. Bit of everything, great weather, it's easy, clean, safe etc. Waikiki sometimes gets a bad wrap as its very touristy but it works so well. Plenty of things to see and wander around, go shopping and eat on the main stretch. ABC stores carry everything you'll need and they are everywhere.

15 minutes away and you are in a different world. Beautiful country, friendly locals with reasonable prices.

It's really worth paying the money for a Pearl Harbour full day tour. The local guides are excellent. The yanks do this stuff really well.

-Haiku Stairs isn't a bad walk.
-Diamond Head was OK but i certainly wouldn't pay for the tour.
-The zoo and army museum are ok for a short look if you are into that. Both a bit basic but we all need to support these things.
- Take your wife swimming with the dolphins. Major brownie points
- Kaluia Ranch. With its movie location tours etc it can be a bit touristy but the fact is its still one of the most beautiful places on earth.
- North Shore, nuff said!! You'll want a car for this. Can be done by tour or bus but it'll take longer.

Heaps of walks, beaches and bays to stop at as well as other touristy stuff you'll see on the brochures. You can't really go wrong anywhere in Hawaii

Not sure what you're into Tuscan, so hard to give too much help. But the one thing I will say is go snorkelling, the turtles are especially awesome. Best to know ahead of time that meals are HUGE so way too easy to over order.

There is some great mountain biking, not sure if that's on the glossy brochures.

mountain biking down the volcano on the big island looks good.

Weimea falls and ala moana mall... hire a standup and paddle down the river at north shore with sea turtles.. paradise cove luau, but make sure you pay for the gold tickets

For Maui, DO NOT take any nice clothes. There is nowhere you won't feel perfectly comfortable in thongs, singlet and boardies (well worn, preferably).

DO NOT even dream of wearing a shirt with a collar. This just SCREAMS "Tourist!!!!!" to anyone within earshot.

Also; the Margaritas at Milagros in Paia are bloody good and they're about a third of the price you pay here in Perth, though you have to remember to tip.

Aloha

Don't forget the outlet mall on Oahu

If you're there on a weekend, see if the flea market is on. Quite interesting if you're into collecting.
I hear the water park is a hoot too.