I know Simpson Bay Resort is improving, but I would pick Atrium. Even if you were to compare to the Atrium prior to the updates they did. I like the location of Atrium better, easier to walk to places to eat and drink along the main road. The staff is excellent and at night it is more secure and in my experience it has always been easier to check in and out at Atrium.

Never sat much at either pool, stick to the beaches.

Both places you could end up with a room with little to no view, so that the chance you take.

Enjoy your trip,
Todd