DC1 got a sushi kit for Christmas one year [this post was started years ago!]. We have used it pretty frequently since.
In addition to standard simple (cooked) sushi using cucumbers or avocado or shrimp etc. we’ve tried some less typical combinations that have worked well.
Chicken salad with sliced or diced apple– this is my favorite
Pepperoni, cream cheese, shrimp, and peas — also good without the shrimp
Refried beans, mango chutney, cream cheese, sliced steak– the chutney really ties everything together.
Strawberries and cream cheese or mascarpone– probably good with other fruit (we’ve had mango at restaurants!)
Here’s the internet with more suggestions.
Do you have suggestions for things we should try rolling up with rice and seaweed?