ck2802 --
I don't know if these things will be happening, and if they are I'm not sure if they will be of interest to you, but it is also possible that the Easter and Springtime-specific activities might be up and running again in 2015. My guess is that the only reason they might not be running is if the events of the 60th anniversary take precedence.
In any case, what might be happening during your trip is:
1. The Eggs-stravaganza -- This was an Easter Egg hunt in both Disneyland and California Adventure. I loved it, and had a great time hunting eggs! (Just like collecting candy at Mickey's Halloween Party is fun for me because it reminds me of trick or treating as a child, hunting eggs for Easter evokes the same nostalgic feeling.) The eggs were large and mostly easy to find (though a couple of them were a tad more challenging than others), which is probably because so many young kids will be searching for them and it needs to be easy.
I am kind of hoping that Disney will expand this idea in the future to include an "easy" level for the kids (with the large eggs), and a not-as-easy level, with smaller eggs that are harder to find, for the folks who want a bit more of a challenge. The hiding places around the parks could be endless for smaller eggs.
The maps/stickers involved in the Eggs-travaganza were inexpensive (just under $5.00 each). They can be kept as souvenirs. but when you have found the eggs you bring the map to a designated location and show a Cast Member, who then lets you pick a small prize. In 2013, the prize was apparently a Vinylmation keychain. In 2014 the prize was a small plastic character egg.
2. The Springtime Roundup in Frontierland. This area was filled with cheery, bright flowers and Spring-ish decorations (wreaths filled with carrots or bunnies, etc.). All of the famous Disney rabbits were on hand to greet guests, as was the Easter Bunny. There were Easter-ish games and crafts too, I think.
The best part of the Springtime Roundup was the "egg art." Just as the amazing pumpkin carvers work wonders with their gourds during the Halloween season, crafting them into intricate, detailed Disney characters, the egg artists used eggs (fake ones), both large and small, as canvases for colorful characters and scenes, or the eggs actually become part of the characters' bodies. I have discovered that Olaf looks good in pumpkin form and in egg form!
I visited the Springtime Roundup and did the egg hunts in each park on Monday, April 14th, which was in the Spring Break time frame this year. It did not feel oppressively crowded at that moment, but I suppose the masses descended upon the parks later.