Try something different with your lighting and exposure.
In this scenario, I also got the safe shot with the flash, but this lighting "experiment" proved to be my favorite shot of the series. It had just stopped raining here, so I took a few shots during the fireworks display with the ambient light. The moisture in the air provided enough bounce for the light in the fireworks, and wrapped softly around the couple. I photographed this at 14mm at 1/8 of a second.