That's good to know. I think I will invest on a 60mm macro setup. I know the theory of strobe positioning, but putting it into practice will be where it counts.
Do the different ball mounts and arms make any difference in how smooth and easy the positioning of the strobes are? my current ones seem very "clicky" if you will, not very smooth at all.
If your strobes have variable power settings i would recommend using those along with manual adjustment of Shutter, Aperture, ISO instead of getting a TTL converter. Depending on the subject color and background TTL may not always give you great results. Also it may not work for getting dark backgrounds. Sometimes images look better with the light being a little under. Just my two bits FWIW :-)
I agree with the higher strobe placement, in fact for both setups. If i understand correctly, this is a dive on a white sandy bottom? If you have the strobes too close to the 9 oclock and 3 oclock position you will end up with bright sand in the foreground. By getting the strobes up higher, with both the further away position and the close up position, you will reduce lighting up the sand. Say 11 and 1 sort of thing
Yes a higher strobe placement makes sense. Also remember that the human eye is used to light from above/top. This may not work if you want to take a head on shot and want to concentrate on getting the teeth highlighted.