Easter falling on March 31st this year consolidates the bulk of Spring Break scheduling to either the week of 3/25 or 4/1. We're less than a month out from that.
Aside from Caribbean beach and some of the DVC properties, there is hotel availability at nearly every onsite resort for both weeks as well as Easter weekend. Further, there is still promotional availability broadly available (All Star rack $234, promo $190 / Coronado rack $377, promo $282 / AKL rack $629, promo $440).
The parks will be busy. I'll be there 3/24-3/28 with performing groups, and expect things to be tight. But the hotel business? Incredibly, unsettlingly light.