At the property now and I figured I'd share some quick feedback and thoughts.
50% of the guests are Russian families with gulf Arab families and American couples making up the rest.
The resort will accommodate a family of 4 (2 kids under 12) in a standard villa. The "Deluxe" villas have an upstairs bedroom so its ideal for a family without going the 2 bedroom villa route. The standard villa indoor square footage is significantly larger vs the W, St. Regis, Westin beach villas. The JW is by far the most family friendly of all the Marriott properties in the Maldives (I've stayed at them all). The kids club is the best run I've seen, my kids actually want to go there! Lots of fun engaging activities. The kids club has its own pool, pirate ship, etc.
Food is on the high end of expensive and has a 8% sales tax & 10% gratuity on top of the menu price. The Asian & Maldivian dish portions are large and can easily be shared between 2 adults with nobody being hungry. The breakfast buffet is very good and lacks nothing but probably the weakest in terms of variety between the category 8 marriott properties in the Maldives, Its on par with the Westin. Food is good regardless of whether its western or Asian. Skip the $50 pizza at the main pool restaurant, its average at best. $15 for a bottle of 750ml water when dining is eye watering. You can bring a bottle of water with you to dinner. This is something that is actively discouraged at the W, Westin, etc from our experience. Kids under 12 eat free from the kids menu at all restaurants. No "one adult meal to one kids meal" restrictions, they can order desert, smoothies, etc with their meals. I have never seen a property be so generous with kids dining. The Sheraton offered something similar but with 1 to 1 restrictions when we stayed there years ago. The specialty restaurants have unique kids menus so its not just "nuggets & fries". The kids club staff also orders complimentary room service (kids menu) dining for all kids at the club! If a little one says "I want a smoothie" or "I'm hungry", its ordered and it is complimentary.
You do not want to be in the over-water villas if there is rain/wind in the forecast. Its been a wet July at the property and the bulk of the guests staying overwater are asking to be moved onto the island beach villas. The over-water villas are also located on the "windy" side of the island.
The water sports center is more heavily geared more towards surface excursions, dolphin watching, fishing, etc. vs scuba diving. That said, they do offer diving and the atoll is full of manta rays! It's rare for them to get experienced scuba divers. The bulk of the diving they do is "discover scuba diving" courses on the house reef. All of my boat dives have been private, quite a perk!
If you are looking for a maldivian island resort experience as a young family, the JW should be at the top of your list.