There are a few ways to go.
If it has to be a conventional politician, somebody to help set up the White House political operation and the Congressional interactions, I would say Kasich.
If it’s another outsider (and I think it would be dangerous to go into the snakepit on the Potomac with two outsiders), I would think General Mattis or General McChrystal would be good.
Your analysis makes sense. I like the idea of the Generals. That would really set the tone.