A veteran of exactly one "Easter" week at Disney here.....
First....I think you have to define Easter week.....the week before (Holy Week) or the week after (the week containing "Easter Monday"). I think it makes a difference....and from reading prior posts, I believe the week after Easter is considerably more crowded.
My experience is from the week before Easter. We found it to be our most crowded visit to Disney....but our prior trips had been exclusively in February and March (non-Easter). Personally, I thought it was only marginally more crowded than President's Day week. I think if you use morning EMH (evening EMH doesn't work well for us, too crowded and we prefer to not be out so late with the kids), arrive at park opening at non-morning EMH parks, and FastPass you will have a great trip. Although I would much prefer February, we will never be afraid of this week again.
One anecdote that you might find illustrative........midweek of our stay, we arrived at MK at the stated park opening time (not a morning EMH day). I don't know precisely what time we arrived at Buzz Lightyear, but we first had to clear the bag check, turnstiles, retreive our wheelchair, and make our way over to Tomorrowland. We were able to ride Buzz 4 consecutive times with virtuallly no wait. We stopped only because the kids wanted to do something else...and the wait time was increasing to about 10 min. Had similar experiences at MGM, but found that TT and RNR tended to back up more quickly.
Best of luck. Remember.....there is no bad time to be at Disney.