I, personally, like fruit rolls using nori. I like that flavor combination. I wouldn't like the fruit rollup as that would be too sweet. For a children's birthday party I bet making "fruit sushi" would be a big hit! Rice krispies bound together with a bit of marshmallow fluff for the rice maybe?
I have made fruit rolls uisng strawberries and cream cheese, another roll using cantelope, and I have even made a roll using salmon, cantelope, and cilantro. Even though the rolls have fruit in them I still like to dip them in a soy-based sauce, something like a ponzu with a bit more orange juice in it. I use the exact same rice I make my normal rolls out of.
Your coconut idea versus sesame seeds sounds AWESOME!
"Count yourself...you ain't so many" - quote from Buck's Daddy