For USD to fall, there needs to be a lot of other fiats that rise. You have more faith and confidence in the other fiat's in comparison to USD?
If they are all phucked, and you are just picking the worst of a bad bunch, then USD may not have that far to fall.
I believe Yuan could overtake USD anytime in the future... China been holding and accumulating gold, contrary to EEUU who only print worthless money paper... In any case, i think FIAT money overall should decline, that system just doesn't work...