While Ranked Pairs sound good in theory, how would you actually sell this method to normal people? Transparency is one of the basic requirements for the acceptability of a vote, and this method will be beyond maybe 70-80% of the American public, if not more.
Well, a lot of them don't really understand the current system either.
What is important is how are you, as a voter, gonna vote for the person you want to win. In the end, it's either choose one or rank them from top to bottom.
What could be the problem is tallying several million individual votes, let alone putting them into a computer. I wonder what the algorithmic complexity is for this system.