I will be arriving to Hawaii for 10 days with the following itinerary
Apr 20: Arrive to Kona
Apr 25: Fly from Kona to Honolulu
Apr 30: Depart Honolulu

I am still confused regarding what hotels to choose on both islands (I am member of Marriott and Starwood programs so choices are limited as this would be reward trip).

Kona:
1) Sheraton Keauhou Bay Resort & Spa
2) Waikoloa Beach Marriott Resort & Spa

Honolulu:
1) Waikiki Beach Marriott Resort & Spa
2) Sheraton Princess Kaiulani
3) Sheraton Waikiki
4) The Royal Hawaiian
5) W Honolulu - Diamond Head
6) Sheraton Moana Surfrider

your comments re what hotels (from the list above) to choose in KOA and HNL will be greatly appreciated. For me, hotel preferences would come in the following order:
- less crowded (if that is at all possible)
- availability of upgrades on award stay (free or by using extra points)
- less families with children
- Quality pool
- Quality fitness center
- Quality beach (but absence of the beach is not a problem if there's a public beach nearby).

Best regards, AX