On vacation, the ability to be up, fed, and at a park at 8AM is an impossibility. We will pick 1-3 (depends on energy levels) days where we make an effort to arrive at a park before normal opening on a non-EMH day.
For example, we got to Epcot about 15 min before they opened - and this was end of July. Even though it will seem like a lot of people, you can get through security before everything opens. Then most people disperse, so we were about to get character photos with Goofy, Mickey, and others within 10-15 minutes. You'll wait longer than that for a much less beloved character in the afternoon. We'd ridden all the FW rides within two hours. In fact, we were the only people on out Imagination train!