Mother Brain - Captain N style

[Ego]

I really like this, if you could integrate the variation in width of the outline that'd be cool, plus giving it a more cartoony edge.
Much as Ego's sprite is competent I think it needs one more darker shade and a slight change in hue (greener/yellow). The chin does not seem to curl up on either extremities, and the eyebrows aren't quite that shape, they tend to curl more on each end. I'm really liking this so please continue!

One more darker shade I can do, and I've been wondering how we should handle to green/yellow color. It should be there from the water, but is there a way to get the color change uniform across everything underwater? The only way I can think of is to create another layer with a solid color that's at, like, 10% opacity.
Or maybe I'll just change to spine color on its own. W/e, I'll just do this for now. Also, thanks for the compliment.