I've a wonderful macro flash unit that I always felt needed attention to detail to get the best out of it. Alas, I have more often simply plonked it atop the camera and hoped for the best.
This unit is known for its leaning towards red values and I think I've found my magic numbers for proper color balance. At least, I'm a lot closer than ever before.
Also needed was adjusting the dual flash heads for location and relative power in order to introduce detail and shadow.