Personally, if you are planning to go after the Poly renovation finishes this summer, I would highly recommend Poly over the GF (and I’m not a Poly evangelist like many on here are). The current GF rooms were dated as soon as they opened and now they are also starting to show signs of wear and tear. The Poly, on the other hand, will have just been refurbished and the mock-ups of the rooms that have been made public look really nice.
Pool wise they are about equal. The Poly has more features and a better slide, but the GF pools are bigger and tend to feel less crowded. Food wise it’s kind of a wash since it’s easy enough to hop over from one to the other (although GF definitely has better and more food options).
Essentially, given the exorbitant rates Disney charges for both (and if anything, the GF tends to be a bit more expensive), it’s really hard to recommend the GF right now with it’s dated rooms for the price that Disney is charging when you can pay the same or less for a much nicer room at the Poly. I’ve always personally found the Poly to be a bit tacky, but the new rooms look great and at the end of the day the GF is still a resort at a theme park. Unless you really hate the kitschy tiki theme or Moana (elements of which have been incorporated into the new room design), Poly is the way to go here until the GF gets the TLC it needs.