OK as someone who has been to the area twice in the past two months and stayed at both properties I will answer your questions and you can make your own assessment

1) QUALITY, SIZE and general cleanliness of ocean beach front; another thread mentioned the Diplomat's beachfront was eroded and very close to the seawall at night (ie not a deep beach, per se)

Beach area at the Sheraton Bal Harbour is a lot better, Diplomats beach area is indeed very very eroded and close tot he beach front at night you heard absolutely correct
2) SIZE of pool area, and is it more a old-fashioned/rectangular pool like the old Holiday Inns...or is it more free-form, with lazy river, several separate pools, waterfalls, etc
Bal Harbour has a waterslide, basketball hoops in the pool a couple hot tubs, water falls and a better overall pool area than the diplomat The diplomat has two pools. The first pool is a baby pool about 6 inches to a foot deep with a partial glass bottom, this is ontop of the bigger pool that has two little water falls. Also during the week half of the diplomat pools area is usually closed because of the conventions

?3) walking-distance to ocean-based contractors (deep sea fishing, harbor boat tours, sNuba, snorkel) nearby ?
At the Bal Harbour you can rent jet skis and other water sports as well as Cabanas at the beach. There is no such thing at the Diplomat
Not a biggie, but
4) cheap eats nearby, so family of five is not eating $40 breakfasts all the time. Will definitely eat on property some, but still need a good pancake house nearby
The only cheap place to eat around the Bal Harbour is a place called flannigans on harding street about 3 blocks down. Otherwise you will have to drive to IHOP or Dennys. If you stay at the Diplomat the Breakfast in the Club Level lounge is more than adequate


I personally liked the Diplomat better but I was there for a romantic getaway. If you are platinum you will get upgraded to a suite. The Suites at the Bal Harbour are wonderful. There are also right at the pool area. I think you family will enjoy the Bal Harbour more but you will need to rent a car