Relaxed sailing in Hawaii is an oxymoron. Of course there are days, depending on the time of year, where the seas are flat, but usually sailing between islands, especially in the winter, is anything but relaxing. Just last week there were up to 50' seas on the north shore of O'ahu and Maui also had some kick but waves in the shores they call "Jaws". Most beaches are closed to tourists during times like this so they don't get in trouble.
Sailing in Hawai'i is not necessarily like sailing in the BVI's. So, be forewarned. Everyone assumes Hawai'i is a boater's paradise. It actually is surprisingly limited when you think of all the water and the few marinas around. There are more sailboats on O'ahu, around Honolulu and Waikiki and there is a newer and big marina complex called Ko'Olina on the Makaha side of O'ahu. There is a Yacht Club in Kane'ohe on the windward side, but it is private.