Hi mpbs,
We have stayed at BWI three times with a waterview request and it has always been overlooking Crescent Lake and the Boardwalk. Overlooking the main pool would put you on the Villas side and I believe the quiet pool would be a Garden view. As you say it is a bit (quite a bit) more$$, so I would double check. All these rooms do not have a balcony - request one with,as it is nice to sit out there and watch the people and boats come and go. A great way to start the day with coffee and a crumb bun from the Lounge by the Lobby. Have a most magical trip!!
Peg and Bob.