It's taking its time but the pose space corrections are about finished. The hard part was correcting the changes, now what remains are linking up the blendshapes above and creating splines for the tendrils on the head. Turning the head has proven tricky but I have a solution of tying the twist and/or roll parameters of the spine IKs into attributes on the body, allowing for easier correction when they twist the body out of shape.
Some of the controls have already been tied in but not all. That is something I am currently working on. I may also need a new system for controlling the fins.now that I have fewer controls along the creature's spine.