We were there for Easter week this year. It happened to be our kids spring break, which is not based on Easter, but is always the 3rd week in April. Not sure if you are going to like this, but the parks were very crowded. We got up early many mornings, hit the parks early, got to do all we wanted and then would relax. We were at the MK and Epcot at EMH rope drop times. The MK was empty, it was 7 am. We have some wonderful pictures of us in an empty park, was like it was all ours. We did all of tomorrow land, some things twice and then went to adventure land for its opening. Did all we wanted, even getting stuck on Splash Mt as it kept stopping. By 11 we were done with all we wanted to do and were able to just wander around, get a fast pass for something and go to it when it was time and just relax between fast pass rides. But the park was packed.
We did the same thing at Epcot, although since it is bigger, it seems to handle the crowds a bit better. But we did all the future world rides early and then just hung out. The second day at Epcot it rained in the afternoon which helped to empty it out a bit, so it may not have been as bad.
MGM and Ak were also packed, especially AK. That was the worst of the 4. But again, we did all we wanted and were probably out of there by noon. it was too crowded to just wander around and enjoy it. You could hardly move.
So, you can enjoy yourself, but I think you need to choose the right park on the right day, and I think you need to be up early at least a few days. The parks will be very crowded.