I couldn't agree with Alex more... the sooner you think outside of the "10-and-2" strobe position box, the sooner you'll come home from dive trips with unique results.
Edward - The shots you posted are great! They clearly show how a snoot can be used to illuminate the main subject, while eliminating stray background light. The background in the snooted image is notably darker, making the cuttlefish stand out more.
Daniel - Great froggy shots! The shot with eggs is a stunner to me - that's been on my wishlist for YEARS now. Great find, and excellently captured. As for why I use the DS160 for snooting - I use them because I have them! They're my go-to strobes for both wide angle and macro photography, so it follows that I use them for snoot shots as well. It certainly does help that they're quick and very powerful (I was able to properly expose images shot at up to around f25 @ISO200), but with the appropriate snoot design (highly reflective internal surfaces, concentrating the strobe's output), you should be able to get away with a FAR less powerful strobe. So, rather than retiring your snoot to a drawer to gather dust, you might want to try tinkering with your snoot a bit before giving up.
Here's a similar froggy image, shot with a single snooted DS160 strobe:
Nikon D90, Nauticam housing, Nikon 105mm lens
1/200s, F18, ISO200