One fear many parents of kids with sensory issues have is that the overwhelming stimuli of the parks might lead to meltdowns that can undermine the fun planned for your trip.
The best way to pace your Disney trip is to plan ahead for how much walking you will be doing and how much demand you will put on yourself physically and mentally.
Disney has multiple apps to make Disney World more fun. One of which, Play Disney Parks, is an interactive app that you can play with while you are in the parks.