The sad fact is that the Grand Hyatt in Kauai is at best a 3.5-4 star hotel and unfortunately Kauai does not really have a 5 star hotel on the island. Stayed many times at the Grand Hyatt Kauai and as a LifeTime Globalist have been upgraded once to the ground floor Ocean View Suite near to the Regency Club - room was musty and smelled of mold. Pretty dark too. Would avoid in future. If the hotel is busy then it is a bit of a zoo with difficulty getting reservations at the restaurants. Our best stay was just prior to Thanksgiving one year when the hotel was running at 50% occupancy - lots of space and we spent a lot of time down at the bottom lagoon which when quiet is very nice. We had an Ocean View King on this stay which had a view over the main water feature.
Food at all the restaurants is average to middling. The Regency Club food offerings are not great although the staff are very friendly. Rates have increased in recent years like a lot of hotels on the islands and the Grand Hyatt is no exception.