now me, im a military planner!!!
this is what works for us, my asd son "leads" the military, we all go at his pace, we plan max 4 hour stints in parks, rope drop most mornings, out either for lunch or just after, back to hotel for swim/sleep and then (sometimes) back to parks, or dinner in a resort hotel, or trip off site - but everything is planned before we go. All restaurant choices are made before travelling both TS and CS, this avoids conflict when we are there, the menus are all checked before hand, so we know everyone will eat off the menu... we always have an alternative in case we work through the park quicker than planned or the menus have changed between us checking and arriving.
this said, after the first week last year we ended up at MGM every morning for a week to ride TOT and TSM!
flexibility is important, but my advice, is knowledge is power, know where the good places to eat are (yes we are obsessed with food, but you spend time relaxing or queing for bad food- your choice

) know the decent snack and where they are available, know quickest routes, which rides to do first etc. if its your first time, no what to avoid, (basically any parks with EMH), decide which parks to do, we avoided epcot on our first trip, but now its our fav park!! use planning videos, plan but be flexible!!
have fun
Tracy