I just returned a few weeks ago from both the HR Maui and the GH Kauai.

The pool and the club are MUCH better at the GH Kauai. The salt water lagoon is very nice. There is amble opportunity for shade at the GH Kauai as you can just take the Tented chairs at the pool if they were not reserved the day before. You can also rent beach-facing 2-seaters with pull over canopy shades for $50/day.

Regarding the beach, at HR Maui the beach has a lot of rocks so it's not swimmable unless you travel down 200 yards or so in front of the other hotels.

At GH Kauai it's a pretty big break with coral and rocks. So it's good for a bunch of locals surfing and cliff diving, but not really for swimming. There is a good public beach 1/2 mile down the road though.

PM me if you want more specifics or some pics that I can share ... -Matt