I've been to Switzerland, and admire the people and the government they run. The point is they run their government, unlike what is being done to Europe now with the EU. It is also unlike any other European state, in that regard, as all of the others are far more Empires than Confederations.
The USA also began as a confederation, but was nationalized in short order. While some states later tried to restore that original confederation during the Civil War, they were defeated, and the USA has become ever more imperial thereafter.
Labels aren't the things they label. There are specific mechanisms that empower the Swiss people to keep the reins of government in their grasp, and one of the strongest is that 10% of the military is required to keep their arms at hand and in good order, ready for action, after they leave active service. Another is that a popular vote of the people requiring a 75% majority is necessary for any increase in taxes. [Not 75% of those that voted, but 75% of eligible voters must vote for the increase, or new tax.]
How would you propose translating the necessary personal rights and individual power retained for centuries by the Swiss people to Europeans that are accustomed to being little more than serfs of feudal nobles, or subjects of imperial states? Perhaps less importantly, at least secondarily, how could such a confederation be prevented from the American fate, and quickly transformed into the kind of imperial nation that most Europeans are acculturated to?
I agree it is a far better way for Europe to govern itself than is being practiced now, or than has ever been done in most European states, but the cultures of those nations are not inculcated with the principles and practices that are requisite to self governance, even in the Swiss confederation model.
Thanks!