I second watching some of the movies!
Sometimes we do Mickey-shaped food to get excited, too.
Do you have a countdown calendar? Those are always fun. We've done everything from paper chains to a little mini chart stand with flip-over numbers. You can use a chalk board or whiteboard, recycle one of those Advent calendars with the little boxes, there are so many ideas!
Having the kids decorate tip envelopes for Mousekeeping is a nice crafty project too.
If you're going to Epcot, definitely find a map and show them where the countries they'll be learning about are! (Maybe even read a little bit about them.)
I also love that you're making journals! I still have them from our old trips, and it's so fun to read them!! We've done dated diary-style ones, but also ones that came with questions, like:
My usual bedtime is _____. During my trip, the latest I went to bed was _____. The earliest I got up was _____.
If you are doing one like that, you could have them make predictions now and then see if the real answers match.
(Other things to include, after the trip, are - favorite ride, favorite restaurant, something that was different than what they expected, hotel and room number, funniest moment, what ride they would invent next if they worked there...)