My dh loves to be in the parks after dark, especially MK, so we pretty much have to do every pm EMH and/or make sure that our MK days are when MK is open late. The kids and I love the am EMH's, so we have to make sure our non-park days are scheduled so we get at least one am EMH per park. Where we'll be each day pretty much helps us figure out where to eat.
Also, we go for longer trips (10-14 days) with 10 day parkhoppers, so we have to make sure to schedule in some non-park days. Once we know which days are non-park days, we can plan some non-park ADR's. It would be a bummer to make an ADR for Le Cellier, only to find out that we're not going to be using a park ticket that day. Hmm, blow one day's tickets on dinner, or cancel Le Cellier? Tough choice!