You can't go wrong at any of them

IMO
Marco Island started nickel and diming a few years ago (started charging for Parking & Chickee Huts but honestly these aren't big costs)...Marco is very family friendly however because of the amount of pools and the large grounds you'll hardly notice them (FYI the Golf Course is on the mainland a few min drive from the resort)

Harbor Beach - personal favorite of Bill's, he and his wife stay here annually

Singer Island Resort - formerly a Starwood Luxury Collection hotel bought out of bankruptcy, current owner/management company is bringing it back up to MI standards but honestly there shouldn't have been much for them to do here....every room here is a 1 bedroom suite, I had family stay here last month and they loved it

Personally everything being equal (which these 3 pretty much are) I prefer Palm Beach, then Collier County and my last choice would be Lauderdale....and given that you get a suite in Palm Beach I'd go there