Yes the main pool is open until 9, the quiet pool is open until 11, however if you are in the quiet pool gates by 11 you can stay in the pool as long as you want.
Though it is large, I don’t think it feels that way. And though we have enjoyed being in a long house that is more central to the pools/main lobby, What’s nice is there are even advantages to being further from the Ceremonial house. if you are staying at the farthest end on one side of the resort, you will be a close walk to the TTC. And if you are on the other end, you can enjoy the beach and proximity to the Grand Floridian. Highly recommend staying at the Poly