We went mid march last year. It was cold and rainy but we had a blast and my girls waited 5 mins for princesses and 7 for Mickey. It was awesome. Probably won't get that lucky again!!
FUnny you are posting this...we went during our spring break this year (MArch 26-30) and it was soooo crowded during 11a-4p time (thankfully we were there early and stayed late)
And for the next trip we too are planning on May The first full week of May specifically.
I would pick the end of May for both crowds and weather. Memorial day weekend will probably be busy but I bet you would get a few really low crowd days too.
We went during Spring Break this year. It was very, very crowded. We also went mid-May, crowds were moderate, but we had a bad experience with a grad night and will be avoiding grad nights in the future. Currently, our spring trip is scheduled for late April.
Do you know how many grad nights you're going to run into if you go in May?