In 2010 we went right in the thick of spring break and it was pretty crowded but not as bad as when we go in August. In fact, the weather was kind of cool/cloudy for a few mornings and they were pretty slow - it was great!
I think you will be there early enough that it won't be packed with families on spring break, but even if it is crowded, you can still manage the crowds - just go early and use FPs.