We're going in April for a seven night trip with our five-month old. With the research I've done and conversations I've had, it seems like the most important advice is to know your individual baby and what he or she needs rather than trying to find tips that apply to ALL babies. For us, our daughter can sleep any place and her nap schedule is erratic but she's an excellent sleeper (11-12 hours straight) at night, so we'll focus on going to bed at a consistent time rather than traveling back and forth to the hotel for scheduled naps during the day. She generally does a good job at restaurants so we won't hesitate to schedule one sit-down meal per day. Other babies might be exactly the opposite, requiring scheduled naps and zero table-service meals.
Some people consider this more of a private topic than others, but if you're breastfeeding and comfortable nursing in public, there are plenty of private and semi-private locations at WDW to nurse. If it's an option, I wouldn't even bother with a pump and all the bottle accessories because that's just an entire new category of crap to lug around.