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Don't rush multiple parks a day, they'll try pushing a multi-park day pass but it's not worth it. Even relatively less busy parks like Animal Kingdom become a chore if you try cramming things in with other parks.
Epcot has more adult things to do, lots to drink and eat at different countries. Always events and live music, most times of year there's always a big band or food/drink event to go to. I'd definitely recommend going here.
Magic Kingdom has the more updated rides.
MGM's a shadow of itself and in a weird point that it's both outdated but also has some modern stuff.
Animal Kingdom is kinda lame tbh. Haven't been there since I was a kid like 10+ years ago but not much has changed.
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Take advantage of resorts/hotels at Disney. There's lots of good food and places to hang out at.
If you want a resort hotel stay at Fort Wilderness, which is camping themed. Great cabins + lots to do like biking/walking and free movies at night on a projector. There's also lots of good food there and ferries to other cool hotels/places connected to the monorail.
Best breakfast/food at a relatively reasonable price is at Port Orleans followed by a bomb breakfast buffet at Fort Wilderness.
The boardwalk at The Swan hotel is great for a late night walk, lots of cool places to chill and nice old-school ice cream parlor. If you go and want to share some icecream order the Kitchen Sink.
If you want good Tex-Mex go to Chevy's which is right outside one of Disney World's main entrances.