Early May is one of our favorite times to go, and we usually go that time every year. This year we are going the middle of May due to one of my kid's college schedule. The weather is beautiful and the crowds mostly manageable. Disney has just gotten busier in general over the past few years, IMO.
Last year? We were there May 1st to May 8th last year, but I remember rain storms all day on Wednesday May 4th that kept a lot of people out of the parks, which made MK a nightmare on Thursday! I remember it because it hasn't happened to us before on other trips and we spent the day visiting resorts and DS. Usually the weather is great with a passing shower the times we've been there.