This time I tried to match the reference a bit more closely, but ended up with a bit less foam. Happy with how it turned out, works really well with iray and the hdri's.
I used an emissive map to fake light passing through (just blended the basecolour with a mask based on the AO and facing normal, minus the foam).
Ymmanuel Who made a cool scene based on the Wind Waker, in which he used my water material (that's on Substance Share). Check the work by Ymannuel here: https://www.artstation.com/artwork/g4oKm
You can now download the substance at substance share: https://share.allegorithmic.com/libraries/2906