Okay, bear with me, I have a novel for you.
You're traveling early/mid December, right? That is right in the middle of peak Magic Kingdom (MK) party season. Every Sunday, Tuesday, Thursday and Friday there's Mickey's Very Merry Christmas Party (
MVMCP) going on from 7-12 p.m., and they shut down the park to regular guests. So, if you're staying at the monorail resorts paying a premium for access to MK, you're going to be out of luck to see the fireworks IN the MK the party nights. Staying Deluxe on a monorail resort line, there's fireworks viewing access at different spots you can utilize, but you'll have to do some homework on that if you don't pay the upcharge for a theme park view. We have done dinner at the California Grill (book the reservation an hour before scheduled fireworks,) and if your daughter is a good eater, the experience is LOVELY on the nights you're shut out of MK to watch the fireworks.
Now, a pro tip if your heart is set on Contemporary/Poly/split stay during holiday party season is to DO MK ON THE PARTY DAY. That's the day to "rope drop," (i.e., get there at least 30 minutes before the posted opening time on the web site,) go through security, and get in line. Everyone will be trying for either Tron or Seven Dwarves Mine Train (SDMT.) Sometimes Space Mountain gets busy, but that ride is a decent people eater throughout the day. Bang out a headliner or two early, OR go against the grain and do all the classics; Jungle Cruise, Pirates, Peter Pan, Small World, Haunted Mansion, Big Thunder, Tiana's, Ariel's (not exciting, but a nice midday break ride,) etc. MK is usually very quiet on a party day, especially in the morning, because day guests don't want to miss the fireworks at the hub and feel shortchanged with the park closing early. This also works if you go during Halloween party season, too, for Mickey's Not So Scary Halloween Party (
MNSSHP.)
If you decide to do a deluxe resort, you get access to special (free) Extended Evening Hours at Epcot on Mondays 9-11 p.m. (great to bang out Guardians of the Galaxy and Ratatouille, sometimes Soarin' and Frozen, but that's a LOT of luck and fast walking.) Do not miss those extra hours! You can get SO much done with such low crowds. Totally worth it! There's almost no food options during those EEH days, so pack food or eat big right before.
This year they're also doing Extended Evening Hours at Animal Kingdom on Wednesday nights from 6-8 p.m. You can definitely do Everest and Flight of Passage, and the whole Avatar area is GORGEOUS at night with the bioluminescent paint on the "world" over there, and the park in general is really peaceful and beautiful at night with soft lantern light.
Hollywood Studios now has their own holiday party,
Jollywood Nights (7:30-12:30) on Mondays and Saturdays, so you have the same issue as MVMCP at MK. Jollywood Nights is new, just started last year, so I don't know how it's going to impact crowds during the day, but just be aware of those party nights.
Hollywood Studios has a free evening open-air stadium show, Fantasmic, (6:30 p.m. on party nights, 8:00/9:30 non party nights,) and it's really great! It's a massive stadium, so you really shouldn't have trouble finding seats, but if you want to be guaranteed seating and good views, you can do a Fantasmic dinner reservation with guaranteed good spots. That's offered Hollywood Brown Derby, Mama Melrose, Hollywood & Vine (I think?) and Sci-Fi Diner.
All resorts have laundry available. The moderates/value resorts, I believe laundry is near the pool areas. If you stay deluxe, it's in the building itself, usually on a specific floor. I think it's worth throwing a load in when at the pool at night.
Speaking of which, the deluxe resorts have hot tubs, whereas the moderates and values don't, at least I don't think so. Pack (or buy!) a bathrobe for each of you to hit the hot tubs/after swimming at night. All the New England/Canadians/Great Lakes folks swim at night "in the cold weather," LOL. The pools are heated to swim in all year long, but they're chilly at night, and I felt funny traipsing through the lobbies wet in a towel. Every deluxe resort sells their own personalized robes, and that could be a cute memento of your first big birthday trip that she could enjoy later on throughout the year.
For souvenirs and stuff, stock up on Dollar Tree glow sticks/necklaces. Buy off
Amazon glow scrunchies if she has long hair. Do get the MagicBand+ for each of you -- the band glows and changes colors during Fantasmic, which is cool, and you'll want the bands to get into pools and stuff and not have to schlep gear down there. I have never had luck opening my room door with my phone or Apple Watch.
We have gone to WDW twice in the first two weeks of December, and wait until the end of your trip to buy Christmas merchandise. If you're going the second week, they start marking down all the holiday stuff 25% in the parks, and you can get her holiday ears, glow Mickey necklaces, spirit jerseys, etc.
Price out day hopper tickets versus buying just ONE annual pass. With the AP you get discounts on all your merchandise, 10% off most restaurants, special entry lane to get into the parks with a shorter line, discounts on BBB/party tickets, and free ride pictures/pics in the parks with the Disney photographers. You don't both need an AP. Just get it for you and you'll be the one who scans their MagicBand (MB) whenever you get a picture done anyway.
Don't sleep on dinner reservations, I think it's 60 days out, plus the length of your stay. So if you're doing a week, you can start booking 67 days in advance, something like that. MyDisneyExperience (
MDE) will list when your booking window opens. Pro tip: Load your credit card information and your party's information in the Friends and Family section of the site way ahead of time. If you want to get those hard reservations, you need all the CC info on file in advance. I think your reservation booking time is 7 a.m. EST, and you want to be online at 6:50 to refresh and book ASAP. Pro tip: Sometimes MDE will quietly let you book a few minutes early those hard-to-get experiences/restaurants.
I truly don't think you'll have time or energy or the need to hit a water park. The pools at WDW are all great -- except at Bay Lake tower and the Contemporary. Just my opinion, but they're pretty lame and boring. We own at Riviera, and ours is pretty boring, too, but our splash pad is really cute and good, and our hot tub location can't be beat to get drinks, snacks, gelato, and the bathrooms.
Caribbean Beach is a moderate on the Skyliner line, and their pool is AWESOME. We totally spent all day at that pool when the kids were little and had a ball. Coronado's pool is HUGE, and the Grand Destino Tower there is beautiful. The resort is geared towards adults/convention goers, but it's really nice, and you having a car would negate the bus issue.
If you're doing a full week and are open to a split stay, Animal Kingdom Jambo is GORGEOUS, especially at Christmas with the decorations. Plus, Jambo has amazing food options in their lobby at all price points, animal viewing areas, tons of activities AT the resort, cultural representatives doing animal carvings and stuff, and their pools ARE great. You can easily walk to the Kidani pool to mix things up if you were bored for some reason, but honestly, there's SO much to do. You'll never get 30% of what you planned to do accomplished, and that's okay! The rides, for us, are totally secondary to checking out all the deluxe resort holiday lobbies/decorations, the vibes, the smells and music. It's so gorgeous that time of year. You'll love it!
To save money and maximize pools/EEHs, and especially since you have a car, I'd do Animal Kingdom Jambo or Poly. Both have amazing pools, tons of activities at the resorts, and you could hit the EEHs at AK and EP with easy transportation. Poly has the monorail at the Grand Ceremonial House/TTC. It's expensive, but I think it's worth it.
Snag in the plans, IF you do a split stay and dining reservations are important to you, each portion of the trip at each different resort counts as a "new" reservation, and so far Disney IT hasn't found a way to merge it into one. So, vacation day 1-4 you book, and three days later you log on to MDE and try to book for vacation day 5-7. People who are booking a solid week will already have had access to booking days 5-7 with their solid trip that is ONE reservation, so your odds of getting good reservations are reduced. You can refresh in MDE when you're in the parks and beforehand at home -- people ARE constantly dropping reservations when the time gets closer, but there's so many moving parts to avoiding party days and reduced park hours, building in transportation time to get to park to park and resort to park -- it's like preparing for battle. I'm a nerd who loves the planning and "scoring" something cool to do, but even after going seven times, I still make mistakes and have missed tons of stuff.
Lastly, EVERY resort has something fun and unique to do. They each do Movies Under the Stars, marshmallow/s'mores, some have scavenger hunts, the deluxe resorts have Community Halls and host arts and crafts projects that are great (and all around $10pp.) Those are good options if it rains.
You can book holiday carriage rides, fishing excursions at Epcot and MK, boat rides right off Poly/Grand Flo, fireworks cruises, tons of stuff. You could definitely book a photo session with WDW photographers, I think it's called Capture the Magic/Moment? It's around $100 for a quick 15-minute session, I think, and the photos come out great! You can pick the park/location.
Check out Ears for Each Other, and you can have former WDW cast members COME TO YOUR HOTEL ROOM and do your daughter's hair/makeup like BBB but at a fraction of the cost. You can get a breakfast box delivered with Mickey waffles/bagels/muffins/fruit, charcuterie boards, party decorations, etc. WDW charges a fortune to do it!
Also, you can have groceries delivered and they'll hold it at the lobby in a refrigerator for you. We do cases of water, fruit, snacks, sunblock, etc. Amazon will also deliver essentials.