I've continued to refine the geometry of the core model. While also dedicating some time today to refining the UV maps to take into account the merged fins.
There is a fair amount of dense geometry but in this case maybe that is not entirely a bad thing in certain places such as the neck or the fins where the body is going to be extremely flexible and mobile. It also gave me a chance to clean up some of the gometry so the model flows much better and more tidily.
As an added bonus, the geometry so far has provided a relatively outline muscle structure which can be further improved with a normal map or a Mudbox pass. Though given I need to skin soon, I might go with a normal/displacement map crafted in Mudbox.
The new UV map has been rearranged a little bit to take into account the changes to the geometry.