South Pacific vs Hawaii

We are trying to decide where to go. Every July-August, we leave home for 6 weeks to travel somewhere in the world. We are a family of 4, with two teen aged boys. We enjoy hiking and snorkeling, kayaking and beautiful scenery. We usually rent a car, drive around ourselves, rent a home and cook our own meals. We have an average budget of $200-300 per day.
We have been to Australia and Austria, to the Azores and to France, to Argentina and Canada.
This year, we are hesitating between Hawaii and the South Pacific. We heard that the Cook Islands are a fabulous destination. Would 6 weeks be too long? Is there any reasonable way of going between the Cook Islands and say, Fiji or Tonga or the Samoa? I researched air passes but did not find much, unfortunately.
Then, we thought of Hawaii. Has someone who has been to both available to comment on which they feel they would return to first for 6 weeks? How do they compare? In beauty, in warmth of the people, on availability of rental places, on easiness of independent travel, on cost of living, on variety of things to do and places to see? Is this a reasonable comparison? Are they similar or thoroughly different?
Thanks for the input!!
Johanne
( we come from Eastern Canada, so airfare-wise, Hawaii is much cheaper, but we don't want this to be our only consideration as we are planning a long trip)

We have spent several long term trips to Hawaii and 2 trips to the Cook Islands( 1 week and 2 weeks). We would opt to return to Hawaii first. We love the scenery, the snorkeling, water sports, hiking and cultural events to attend. You have the option to visit several islands, each with their own different vibe. The islands are larger and so you have more variety in things to do, with plenty of beaches to discover. The Big Island also gives the opportunity to explore an active volcano. The only area you might find lacking is in the warmth of people as the Cook Islanders will be more welcoming as Hawaii is like living in Canada in many regards. Hawaii will not have the lagoon of Aitutaki, which is quite beautiful. I think the only option for travel to another island group would be French Polynesia as Air Rarotonga does 1 or 2 trips per week. As for costs, they are probably similar. Hawaii is often considered expensive but we have found you can find reasonable prices with a bit of research. If you would like more information please PM me.

I'm the opposite. Hawaii doesn't represent the South Pacific (it isn't even in the South Pacific) and the original Polynesian culture has pretty much disappeared. What is on show for tourists is just that, for tourists. It is more like vacationing in tropical US. It is pretty, though and the islands are varied. Cook Islands are far more traditional even though Rarotonga is possibly one of the more westernized areas of the S. Pacific (not been to Guam, etc. so have no comparison there). Much friendlier as well, as is most of the South Pacific. All I've heard about French Polynesia is that it is beautiful but expensive; again, I've not been there so can't offer any opinions.

I flew between Cooks and Fiji with no problems, as well as between Tonga and Ind. Samoa (direct flight Vancouver - Tonga); the Tonga/Samoa trip was back in the mid-90's so I don't know how flights may have changed since then. A reputable TA will know, though.

We live in New Zealand but also own an apartment in Waikiki and spend at least 3 months there each NZ winter.
We also take about 3 shorter holidays a year closer to home in the South Pacific either Fiji, Samoa, Niue, Tonga, Vanuatu, Cook Islands or French Polynesia.
In a lot of the islands there are very few private rentals compared to Hawaii, in Fiji for example the only thing that may be on some of the smaller islands will be a resort and there is no private accomodation that would be available for rent.
There would also be nowhere to buy food to cook for yourselves.
We have stayed in Samoa for up to 6 weeks and as we mainly like to snorkel and walk we were not bored but usually only stay about 10 days at smaller islands and sometimes string a few resorts together for variety.
Star Alliance (AirCanada and air New Zealand) fly from Canada to Hawaii and on to Fiji, why not spend a month in Hawaii and then 2 weeks in Fiji at an island in say the Mamanuca's to get a taste of both. A months vacation rental in Hawaii is probably around US$2000.

I must admit to favoring the Cook Islands over Hawaii. I write a guidebook on the Cooks and any resemblanse the two share has been removed over the last 100 years. Hawaii is Los Angeles on an island. Hawaiaan hula is to Cook Island Maori dancing as is Taco Bell to Mexican Food. Rarotonga is what Hawaii was like 75 years ago. More tourists visit Hawaii in a day than visit the entire Cook Islands in six months. Apples to Oranges, folks!
From Canada you will spend twice as much getting to Rarotonga, but half as much once you get there. Friendly people and authentic Polynesian culture,

Papa Mike

"I flew between Cooks and Fiji with no problems"

Just want to note that there used to be a flight between Fiji and the Cooks but there no longer is.
Now one has to travel via Auckland to get from the Cooks to Fiji or vv.

I would take a look at the temps of the various south pacific islands during July/August. It's winter there and perfect (high season) weather in French Polynesia but the Cooks or Tonga might be too cool for some who like it HOT, HOT, HOT.

Well thank you to you all!
your messages have been well taken. We are now seriously considering spending half our time in Hawaii and half our time in Fiji.
Papa Mike, I hear you. I have put the Cook Islands on my list but thought I would go when we visit New Zealand.
Thanks again for your inputs!
johanne