I don't know. So far, we've only done humanoids that one can find in every fantasy mythos. Now we're getting down to enhancements on the prior art as the ol' OGL would say.
Now that all the humanoids (and the giant-kin) are taken care of, maybe we should start getting down to the other kinds of monsters. The problem is there are so many different kinds of classifications. Planar creatures, prime creatures... who knows.
Let's start off with something simpler and then work out way down to golems, outsiders, dragons, saurians (like the lizardfolk & troglodytes), and the like.
How about aberrations? It would be convenient to go in alphabetical order.