Prepare the meatballs: Preheat oven to broil with the rack 6 to 8 in. from heat source. Line a rimmed baking sheet with aluminum foil, and coat with cooking spray. Set aside.
Stir together chicken, egg, onion, panko, cheese, oregano, garlic powder, salt, and pepper in a large bowl (do not overmix). Shape mixture evenly into 24 balls (about 1 Tbs. each), and arrange 1 to 2 in. apart on prepared baking sheet.
Broil meatballs 3 minutes. Remove from oven, and flip meatballs. Return to oven, and broil until a thermometer inserted into thickest portion of meatballs registers 165°F, about 3 minutes.
Prepare two skewers: Trim tops and bottoms from bell peppers; remove seeds and ribs and flatten bell peppers. Trim red bell pepper into two 1-in. triangular rocket noses. Trim orange bell pepper into two 1-in. flames. Thread each red rocket nose onto a 4-in. skewer (cutting off sharp points first), then add 2 meatballs. Complete each rocket with an orange flame.
Freeze leftover meatballs in zippered plastic bags (4 per bag) up to 2 months. For lunch the next day, transfer frozen meatballs to the refrigerator, then make and pack skewers in a lunch box in the morning.