Nice. I love the changes Magikeeper made to the Stomach, and I also think the new fin feature is awesome. Advanced Form is a cool idea, and I like the idea of increasing form points gained as capstone.

Like... maybe for capstone, instead of (level*3)+Cha+Aberrant Feats, capstone could change it to (level+cha+aberrant feats)*3, so the charisma modifier gets multiplied in too. So a level 21 Ozodrin with 22 Charisma and two aberrant feats would have 87 form points.