Sharpness is great, light is soft and the composition is good. Also Ilike the soft pink and green colors.
This image has a scientific look to the image, that is, it does not look like an image created in the field.
If this was the intent than it is a success. If not than you can use an ambient light aperture setting (shutter speed is not important) and turn the flash way down to balance the flash with the ambient light. Or set the exposure on the camera manually for the ambient light and set the flash to ETTL and use the flash comp to control the output.