Both you and WOSG want a "constitutional requirement" on residency, and I'm here to tell you (and you really know this, don't you?) that it was such COMMON KNOWLEDGE that the representatives would not come from another state that they didn't even bother putting this stuff in there. It's like the notion (pre-1913) that any money would ever be issued without gold backing. It was just nuts.
But go ahead. Let's get Keyes nominated, then he'll get whipped badly, and the next time it's going to be some elite Hollywood type who has name recognition and lots of money blowing into Nebraska or Wyoming and you guys will be crying in your beer. Have at it.
There is nothing immoral about a state deciding the best man for the job is from outside. If they don't want an out-of-stater, fine. If they do, it's also fine. It's up to them. The Founders would never have imposed on the states any idea of whether this is right or wrong. They left it to the states to decide.
It was also "common knowledge" that women wouldn't kill babies. Hence they didn't write in any restrictions against it.
It took the Supreme Court to find that "implied right" in the constitution.