You will be visiting for the big celebration. How exciting!!!! I'm sure the crowds are going to be a bit higher than normal due to this. So, being prepared for that will help. Also, they haven't been announced yet, but there most likely will be press events that week. Which may close certain attractions or whole areas of parks off to you. They don't usually announce these until the last minute though, so keep your plans flexible.
If you are staying onsite look into working EMH into your schedule. This would dictate which days for which park. If you don't want to use EMH or you're off site then you may want to use the after method. Meaning you go to a particular park the day after it's EMH. Statistically it's a less crowded day. Since the EMH days are still not set in stone, it's hard to say which day where until that schedule comes out.