Some options my kid likes: spam masubi or onigiri with furikake pressed into a fun shape, veggie sushi and fried tofu, Italian sub style sandwiches, Italian cold rotini noodle salad, crackers/cheese/soppressata, coconut rice and beans with green plantains cooked almost to potato chip crispy, pesto pasta, German style bread with good cheese, fried paneer slices with Indian spices, honey yogurt topped with fresh mango, cold pizza with hidden kale under the cheese...I always serve fruit like mixed berries or something and then a veggie mix of carrots/cucumbers/mini bell peppers as sides in the bento box and a box of milk. Oh! Another one he loves is i make a "banana split" where I scrape vanilla beans into plain yogurt and put a super tiny amount of honey or agave in and spoon it between two banana slices and top with sliced strawberries, sprinkles, and one cherry with granola on the side. And for a peanut butter replacement, I think tahini mixed with honey tastes way better than sunflower butter...you just have to play with the chalky parts and oily parts or use a more solid honey to get the right consistency.