I found that setting my preferences was mostly a PITA afterward. The only good thing was that then my main selections showed at the top of the Tip Board and I didn't have to scroll down, looking for them.
But once you do that Genie thing, it populates My Day with a lot of useless (to me) suggestions that appear above one's actual reservations.
It's unbelievable that the Tip Board doesn't know what park you've got a reservation for that day and doesn't just default to that. It always defaults to MK unless you've Genie'd it up. Furthermore, even though it knows you have a G+ or ILL$ for a particular attraction, the Tip Board doesn't show you your time. It only shows you available times, if there are any. No, you have to go to My Day for that.
There are about 100 things that need to be fixed, and that's not even counting the things that should be fixed--like being able to modify one's G+ or ILL$ if a better-for-you time appears--just the ordinary things that fit within the current G and G+ systems that are illogical and anti-intuitive.