So, interestingly, if you look through Fantastic Four analogues, Thing and Human Torch convert into any powerhouse and some type of elemental power. Mr Fantastic is more directly associated with his intelligence, and Sue is just female. Which kinda works since you can throw any power on her from there. Adding some variety. Neon Queen having the power to take a gaseous form.

Sculpted up the belt and hair. From there, just a repaint, and all done!