There is nothing wrong with taking a trip to a Disney World park or any Disney park for that matter without having a set plan of attack. Winging it is perfectly fine.
So you have made the decision to visit a Disney theme park and now everyone is telling you what you need to do before you get there. You need to buy the Genie+ when you arrive at the park, you need to preplan your morning at the resort, you need the meal plan if it is being offered, and you should probably buy this, this, and of course, that.
Guess what? You don't need to do any of that. You can literally walk through the front gate and have a great day without a single plan in front of you.
Other Disney sites will lay out the plan for you. They will give you the what's and how-to's. Many will tell you to get with a vacation planner because they can plan your trip out for you down to the minute details, but no one can control everything and sometimes, plans don't go the way you want.
Nothing will make your life more miserable than having a plan of attack when you hit the parks. You know where to go, when to go, and what you are doing...then a ride shuts down, the weather turns, and suddenly your plans are running behind.
I'm not saying you shouldn't look into it if that is what you want to do but winging it sometimes just as much fun, if not more.
Disney is fun. Doesn't matter what park you go to. If you are walking through a park and see a character you wanted to meet and didn't know was there, you can detour and meet that character. Notice that ride times are lower than expected, go ride it.
I have realized from my year's of going to Disney World that I don't need to know what my day is going to be. I make it up as I go. Sometimes I spend my day at EPCOT more in World Showcase where other times I don't. At Magic Kingdom I have left Tomorrowland and headed to Frontierland only to turn around and go back to Tomorrowland.
What is really cool is that it is completely allowed. There are no restrictions.
That doesn't mean having a plan isn't smart or that it is restrictive but you shouldn't live by it. Meal plans are great for some people but what if you decide that you want to eat something that isn't covered in the plan...will you skip it because you spent the money?
Many of my friends have gone to Disney and some will go the "save money" route which is smart and some go the wing-it route and that is fine too. In both cases, they have a great time but I have noticed that the pre-planning stages are a lot less stressful for the "wingers".
The only plans I make when I go to Disney World now are the parks I will visit on which day because they required reservations. I will get up in the morning and try and get a queue pass for a ride like Guardians of the Galaxy which is the only way you can ride that attraction.
Other than that, I get up and head to the park when everyone is ready and when I get there, I let my kids pick the direction we go first. If a wait time is too long, we do something else and come back to it later. And you know what, we have a pretty good time doing it without worrying that something might get messed up.