Oh my goodness! I was just thinking about this today. If we could just incorporate the building structures from Primitive plus, it would make so many people happy.
My favorite mod besides Structures + and CKF is OzoCraft. I wish we could have those structures even more. The guy that did that mod really knew what he was doing. It works so nicely in Ark. He put in the pieces that we are missing for building more detailed builds and the textures are just gorgeous!
The bottom line is that we need more building structures in the base game. I would much rather have new structures than new creatures any old day of the year!