At one time in the recent past, Sleepy Hollow also had another one (other than spicy chicken or fruit/Nutella) that, as I recall, was prosciutto (ham) and cheese. They also had a breakfast version with ham, egg and cheese. We have had both (plus the other two), and both could go down easy for someone who might be relatively picky but could otherwise enjoy a ham and cheese sandwich. There is the usual lettuce, tomato, etc., but that stuff would be easily removed (or left off altogether).
Sleepy Hollow's waffle sandwiches have become a go-to spot for us, whether for breakfast or lunch. To my knowledge, SH is the only place with something like this. We ran across a buffalo chicken waffle at Animal Kingdom, but that would be even a little farther off the picky-kid radar. For what it's worth, both of my kids enjoyed the "spicy" chicken one and didn't think it was particularly spicy...but both still prefer the fruit and Nutella option, as well as the prosciutto/ham and cheese, so I can understand the potential need to wade in gradually!