If you have to pick only one, then Poly.
We did a split stay at AOA and the Poly on our first trip. If you're staying 6-7 nights, a split stay is no big deal with 2 nights at AOA and the rest at the Poly. Bell services will move your luggage for you but it won't be available until late afternoon, so keep that in mind.
The suite at AOA is great. We LOVED the room and having 2 bathrooms makes life easier. We discovered that we don't like food courts, especially with young kids, but yours are old enough to go to the bay of their choice and magic bands make paying easy. Buses are the only transportation option unless you'll have a car. They were fine, though.
We splurged for CL at the Poly (our anniversary present to ourselves). Loved the variety of dining options on the monorail loop, the transportation options, and the volcano pool. The rooms are large, the compound is very manageable for walking to the main building, and the walk is gorgeous with all of the neat plants.