I do make plans for every day at WDW, and on the meal reservations I allow one hour for each meal. If I have extra time, so much the better. My personal plans for each day always allow extra time. That way, when I have time to spare I can do something twice, or, simply relax, have a cool beverage somewhere, and people watch. If you make your plans too time demanding, counting on doing things in a set amount of time, you will find that it won't work. And you will end up not having as good a time as you would have had otherwise.
Enjoy.