What they have done in the past:
1. The resorts have Easter Egg hunts Easter morning. As noted above, those can be very crowded. Usually there is an Easter Bunny (BoardWalk also adds some craft events).
2. There are some additional Easter decorations but this is not treated like Christmas. Most are hardly noticeable.
3. There is an "Easter parade" which is really just the daily parade at 3 with some Easter themed floats added; generally runs entire week before Easter and on Easter.
There ain't much else as Disney mainly treats Easter time like any other spring break week. Also, unless you like elbow to elbow crowds where you can hardly move, you should not even think about going to MK on Easter Sunday. Pratically everyone goes there on Sunday giving the other parks one of thier lightest days of the holiday season. Moreover, most go to MK that day under the false impression that something happens there on Sunday that does not occur on other days. In fact, absolutely nothing goes on at MK on Easter Sunday that you cannot see another day during that holiday season.