Turning the circuit on/off could be much easier with a slide switch mounted somewhere on the outisde of the prop. Currently, the circuit must be taken out of the magazine to turn it on/off and put the wiring at risky of being damaged.
Want to make this project a gillion times better? This project could definiately use of an accelerometer, vibration switch or capacitive touch. Instead of the pushbutton triggering the NeoPixel animation, the force of acceleration or the jult of viberation could trigger the light. The easiest way to get a more interactive actuation is to use a vibration switch in place of the push button – it's basically a drop in replacement.