I follow Mesaboy2's advice religiously and pick the rides I'm interested in, prioritized according to what he lists as most "important/necessary" for FP. Since I usually plan 2.5 MK days and 2 Epcot days AND Frozen is the newest thing, right now I'd probably go after my Epcot Frozen day first, then look for a MK day with 7dwarfs, then back to my second Epcot day with Soarin as priority, then proceed with more MK and the other parks.