I would totally go for Poly and not bother with a split stay. I've only been to Poly for dinner at Ohana, so I don't know if there is another pool other than the volcano pool -- I'm sure that would be easy to find out -- but, I loved the whole feel of the resort, looking across the water and seeing Cinderella's Castle, the girls playing in the sand on the beach...you make ME want to stay at Poly!!! The small tradeoff of not having a washing machine in the room would matter very little to me in the long run and few times in the past when we've elected to stay somewhere with a kitchenette we wound up using it very little, so I don't think you'll miss it. But, that's just my two cents. Whatever you decide, have a wonderful time!
Riding Splash Mtn at Tokyo Disneyland for the first time as a family!
Nobody had to stay behind for Parent Swap!