We have a few pieces from Coral Casual and like it very much. When you order cushions, specify the outdoor, quick dry cushions. We have a few on the floor for pets and they occupy them shortly after rain storms. Water doesn't stay in them, but they are cushioning. A bit expensive, but sounds like what you want. I also order from
Cushion.com Lets You Customize Replacement Seat Cushions and Outdoor Furniture Cushions