Hi Clawdeen
We were there over Easter hols, which coincided with spring break, so the first week the parks were very busy, but it was manageable. You have to be prepared to plan well in advance so you can prebook fast passes and get there for when the parks open. Second week, walking around the parks still felt busy but the queues were shorter and not so busy at mealtimes etc. when we went to universal in the second week, the park was nearly empty until lunchtime.
Weather was hotter than expected. I had thought that early April in Florida would be mid 20s (results of a few google searches) but it was over 30 every day. Some people told us it was unusually warm, others said it was normal for that time of year.