First, I must confess that the Poly is my favorite themed deluxe at WDW. Having said that, it also has a number of tangible benefits for your family.
It is a monorail resort. That means quick on and off for the MK. When our DKs first went to WDW at 5 and 7 (off-site stay), they tired out by around 2 and the rest of the day (and evening) was more like triage than touring. By the time we next went, we stayed at the Poly. Now we could plan for an early start, an easy 10 minute ride back for naps and pool in the mid-afternoon, and then back to the parks by 3. It changed everything. Plus, the TTC is less than a 10 minute walk from the Poly, so we could get anywhere else in WDW very easily.
We did not use it, but the Neverland Club is available for you and your husband to get some time alone. But even if you just want to enjoy a romantic walk on the beach (with a shared Lapu Lapu) or a great dinner at Artist's Point at WL or V&A at GF, you can easily get babysitting at the Poly.
It is just my opinion based upon my experience. But for so many reasons, the Poly wins hands down for me.