We just returned from a fabulous stay at the Polyneisan.
That beach where you can see the castle was just outside our room.
Don't get me wrong.............that view is PHENOMENAL.
But if I'm not actually in the Magic Kingdom and want to see the fireworks, I prefer the view from the California Grille at the Contemporary.
It's a lot closer, they pipe in the music if you stay inside, etc.
Just a matter of personal taste. There's certainly nothing wrong with the beach at Poly.