Permit me to tack one additional point onto the book-length dissertation below.
In a scenario in which there are no great options at the top of the ticket, it’s important to consider who the vice-presidential candidates are. This is especially so this time around because I believe there is a much greater than normal chance that, whichever candidate wins, he or she will not serve a full term.
Both Mrs. Clinton’s mysteriously volatile health and long-standing habit of ignoring the law mean her term could easily be cut short. I also find it easy to imagine Mr. Trump quickly getting fed up with the suffocating constraints and crushing burdens of occupying the Oval Office and simply walking away, claiming that he’d proved that he could win.
In either case, the running mate becomes President. The good news for those pondering a vote for Trump is that his running mate, Mike Pence, is a exemplary human being and would make a fine president.