For a very light snack, there are icy type drinks all over WDW. I don't mean smoothies, but I don't know what they are called - kind of a fruity slushy kind of drink that is great on a hot day. The stand across from the tea cups had some good ones and the tea place in the AK had some great ones! Those are the only two I had. Next time I go, I will have more because I now know they are available everywhere.
Oh, if you like a popsicle, the Itzakadoozie is a fun treat!
How about a funnel cake? Or creme brulee? (Can you tell I'm hungry?)