Why would those make a difference? The US elected the same corrupt madman twice. Why would things suddenly improve after this election?
If both houses switch then he will be distracted fighting them for the rest of his term; if they don't we no longer need to treat the US as a functioning democracy.
And then what? Things will magically go back to the way they were? I doubt it. The US has seriously damaged its international reputation. It has burned bridges. It has started literal wars. Removing the Orange Danger would be a good start, but it will by no means by the end the problem.
Exactly. Trump isn't the problem. Trump is a symptom. I'm far more terrified that the US will sigh and go "puh, glad that's over and will never again be a problem" than I am of Trump.