One thing we do that I haven't seen mentioned yet is we ship a box down to our resort ahead of time. Babies & toddlers need lots of supplies & I don't like bringing tons of luggage. I ship (thru UPS) diapers, wipes, disposable sippys, snacks, swim diapers, Wet Ones, disposable spoons, disposable bibs, etc.
Also, fireworks are loud & can scare little ones. We don't stay for them, but will watch them from somewhere else like Poly beach, Narcoossee's, or California Grill.
Don't try to do everything. Go at little one's pace & take breaks.
Let her have a Mickey ice cream bar!
My DSs got their own plane seats as toddlers & we use CARES harness.