I would rule out MCH because Aeropuerto General Manuel Serrano Renda is in Ecuador and clearly out of the way.
While I cannot complain about ZRH, I would mention an airport you didn't list, MUC (Munich) which is considered by many one of the most efficinet airports on the Continent.
While you cannot go wrong with either ZRH or MUC, perhaps you should strike FRA off the listi (and forget completely about the Ecuador transfer !