We just spent a week of our honeymoon there, and really enjoyed it. Granted, this was a timeshare trade as a gift from my parents, so we were only paying for incidentals, therefore, I don't know what the rates were or anything like that and if we would have been paying too much for our room if we were paying.
We stayed in a 1 bedroom villa with efficiency kitchen, which was quite nice. The room was very clean, and the only issue we had was a cracked glass, which was replaced immediately by housekeeping once we reported it. The furniture was comfortable and nothing looked shabby to me. We were in a room that was at the end of the Molokai Tower, facing the mountains, but also had a view of the ocean. We could see both Lanai and Molokai from our balcony.
Sure the lobby is a little blah compared to others, well, it's open to the elements, so they can't put too much stuff in there that could be destroyed by rain. There were some fountains and sculptures that were nice. The section of lobby that was in our tower was absolutely stunning, but I don't stay at hotels based on the appearance of a lobby. We did check in the evening and the lobby area did not look as impressive until we went down the next morning and saw everything in daylight.
We were there about a week after the previous poster and only noticed a few kids, and they stayed mostly by the waterslide and by the lower pools, so that wasn't an issue. Marriott's are family resorts, esp. when you factor in that it is a timeshare, you're going to get a lot of guests with children. Stay somewhere else if you're going to be bothered by children in the slightest bit.
Another bonus for us, the laundry facilities were very nice and clean, and perfect for us since we had been travelling for a week prior to arriving in Maui.
Also, Whaler's Village being within walking distance was great.