I would load up on GF direct, honestly. The promotions they're running now are really good. It'll be stunning for this December at the holidays for the kids to see the decorations in the lobby, and the
DVC original wing is down a walkway, away from the madness. SO pretty.
I don't see the resale points being that off from direct, and while APs aren't for sale currently, I do think they'll come back. With 3-4 kids, at a savings of $300 per person, that is a great perk when it comes back. Also, GF is GORGEOUS and convenient, and the rooms are all large. Their splash pad for littles is adorable.
BLT may be closer, but I, personally, really didn't like how it's laid out and found the kitchen setup very weird and small with the island. GF has a nice wet bar/drop zone for diaper bags, gear to run out the door in the morning. The kitchen is laid out great in an L with plentiful cabinetry, and I like the booth-style dining for kids. You can easily slide a high chair along the table to the side and feed the other kids in the booth. If I recall correctly, the foyer area is large enough to park a double stroller, too. I know Riviera has a huge foyer that we easily parked my husbands
ECV last trip (got knee replacement two weeks after we got home from WDW.). Definitely could have fit our old double-wide stroller over there, and I am pretty sure GF is even larger than Riviera for that stuff. Storage is plentiful.
Studios would be a nightmare, IMO, for you guys to pack all the baby gear and strollers and dealing with different nap schedules at these young ages.
With a one-bedroom (and larger,) you have a private (large) bedroom with a king bed for your husband and you, and you'll have plenty of room for a pack n' play for naps in the middle bathroom area or in the room with you for a newborn/younger baby. There's no way you can feed everyone and keep them quiet while others need a nap or flame out early in a studio.
And, Florida gets rain -- often. There may be days you are rained in and stuck in the room, or someone gets an earache or gross cold on vacation and is hacking all night. You're going to want to kill yourself if you're all on top of each other with no space to amuse the kids coloring or having snacks and dealing with a sick kid. S*&# happens, even in the happiest place on Earth, LOL, why not be prepared, just in case?
Also, having the full kitchen and laundry in the room are game changers. Even if you plan to mobile order most meals, you're still in the bottles/baby gruel/cereal ages for another few years. You'll want a real refrigerator to make bottles, store milk and simple breakfast staples and snacks, and it's awesome to throw a load of clothes in at night when everyone's showered in their jammies and you aren't throwing spit-up clothes and sweaty gear in a trash bag to schlep home. We only travel with carry-ons and now only need 3-4 outfits per person/kid since I do laundry each night. It's way easier.