Eh...McClain County's my stomping grounds. People around Washington (which is more or less due west of the proposed southern terminus of the Kickapoo) simply do not use SH-9 for a trip to Chickasha; the preferred routing is SH-24 to SH-39. I'm not really sure where you'd take a turnpike west from the current southern terminus, though. Once you get past Washington, you start getting into some pretty thinly-settled territory; there's really only Dibble to the southwest. There's a whole lot of nothing between there and Chickasha.
McClain County and the Goldsby/Washington area is growing, slowly but surely, but most of the growth is concentrated along the SH-9 and I-35 corridors right now. There are some new homes going in closer to Washington, but for the most part they're one-offs from someone splitting an acreage off of a quarter-section or something like that, no big subdivisions like north Goldsby is starting to get. The area between Dibble and Chickasha might sprawl up in...oh, say, fifty years, maybe. The only thing that would move that up is if Oklahoma City becomes the national capital and also the global headquarters of a merger between Amazon, Walmart, and Boeing, someone strikes gold in Dibble, and Kevin Stitt is succeeded by the ghost of Franklin Delano Roosevelt.
My wife lived in between Dibble and Chickasha when we first met in 2011. At the time the cell signal was so weak you had to go stand next to a window to get any reception. One time we had to call the Grady County sheriff because someone's horse got loose and ended up on her roof somehow.