We had 12 people (10 adults and 2 kids) spanning 4 generations. The oldest was 80, and the youngest was 2. Everyone had a different lifestyle, mobility, and interest. This was a perfect vacation for all.
The older family members stayed in the cottage and loved the privacy yet feeling part of the action when they wanted.
The youngest members were located by the master bedroom, so didn't wake up the others too often when they needed a nap/early morning wake-ups.
First, the views were amazing. The master bedroom had massive windows that overlooked the beach - it was my favorite thing every day to just sit on the upper porch and watch the waves roll in. The rest of the family really enjoyed just hanging around outside, opting more to stay at the house for the views and relaxation than going anywhere else.
The layout of the house was great for those wanting to spend time with other family members. We made use of the BBQ and the outside table frequently.
My two sons loved having both the beach and the pool feet from the house as they each liked a different one (the waves were very calm the entire time and manageable for 2 and 4 year olds with supervision). The heated pool was a must and was a daily routine. The tennis court was also a big hit for the kids.
The middle generation (all in their 30s) were able to get around the island easily, taking day trips to North Beach, Hanauma Bay, Pearl Harbor, etc. Everyone also had the ability to have date nights with all the great recommendations in the area.
For the athletic people, the main street is perfect for biking and running. I woke up almost every day and used a rented bicycle to go to Diamond Head crater over to Wikkii beach. It was both good exercise and a beautiful view.
Overall, one of the best vacations I've ever had. I would highly recommend it if you can afford this house. Note that the pictures do not do it justice. While some of the furniture is dated, the house is in excellent condition, but the views are much more amazing than the pictures convey.