Actually I believe Brookies are the only trout native to Missouri. I believe, however that they died out a few thousand years ago.
I have heard, but not sure how true it is, that Brookies are less tolerant to high temperature and to low DO.
Cutts are another animals, but I'm not sure what advantage they might bring, other than for Taney where they might disperse better.
I'm not sure about that report Brian. I've been around Kokanee and they don't get that big, and they aren't predators. They would however be a poor choice for Taney, at least in my experience with them.