We usually stay at Deluxe resorts (GF, WL, BW, Y&BC) and our last trip we could not afford it so we tried out POFQ. While the theming at PO in general is quite nice, you get what you pay for. The rooms were comparable, but not nearly as nice as Deluxe. In general we found the maintenance of the grounds to be sub-par, and the options for dining and entertainment were very limited (there is a boat that runs to DTD but it shuts down too early to really enjoy it IMO.) For my money, the Grand Floridian is easily the most beautiful resort in WDW. Just being there always gives me a sense of awe and relaxation. The grounds are beautiful, as are the buildings and the beach. Since the Polynesian is similar in price, I recommend against it. I know some people swear by it, but it has been by far the worst hotel we've stayed at in WDW. We hated it so much we actually switched over to the GF. The Boardwalk and Y&BC are also similar in pricing. They aren't quite as lavish, but they have a wonderful charm all their own and their location is tops. Nothing quite matches the feeling of laying out on the beach, staring out at the majestic boardwalk, or vice versa and lounging on the boardwalk and enjoying the reverse view! This area has by far the most entertainment options in a resort area, and the location makes it every bit worth the price. Being within walking or boating distance to both MGM and EPCOT is an awesome feature. The WL is also wonderful, but I won't go on about it since you've already stayed there.
As far as xmas decorations, I've been at all of the above (minus POFQ) at christmas time and they all have wonderful displays, but the best is hands down the GF. Honestly though, the ammount of money you're talking about saving is a big deal. Maybe to you a hotel is just a bed in a room. It's not like any of these places is a slummy motel, they are all Disney Quality. My advice is to think about what you want in a hotel, then figure which is best. Where do you want to be located? What kind of ammenities do you want? What kind of things do you want to do? What theme do you like best? You may also want to think about what you would do with the extra money you'd save and weigh the importance of that vs the hotel.
One last thing to consider might be the Fort Wilderness cabins. These are good options for long stays because they have kitchens which can save big money if you use them.
Regardless of where you stay, you will still be at WDW, and I'm sure your trip will be wonderful. Have fun planning!
