As much as I like the GF, if you have to choose between a standard and Poly concierge, I'd definitely go with the Poly. We caught glimpses of the volcano pool and it looked great. There was no underwater music at the GF pools. As for splitting the stay, depends on whether you guys make yourselves at home in the room as much as we do. All of our stuff comes out of the luggage and backpacks. I can't even imagine having to repack in the middle of the week, even with staff help.
I haven't stayed at the poly, so I'm not sure what they have for food, but Gasparilla's at the GF is nice. It's counter service with video games inside, but the food is surprisingly good and not expensive. They had everything from pizza, cheeseburgers to taco salads and chicken parm. Even had make your own ice cream area.
I've heard great reviews about the poly and our experiences at the GF have been very nice. Whatever location you decide on, I'm sure you'll have a wonderful time.
Tammi