Overall the EU is imo enormously succesful for the lifes of the people living in the EU.
And from mainly economical power we can protect many standards of life of which most people outside the EU+ can only dream.
But
In the South countries established politicians, newsmedia, movement leaders bombard their people with vocal rhetorics on "the great injustice" being done to them by the North.
On top you have the usual sentiments and convictions that the Brussels technocrats are bad technocrats and supporting the power and interests of the big multinationals. The anti-establishment attacks.
This has been going on for decades by now and on top the des-information tools have become stronger.
The intention of the Euro that it would help convergence does not seem to work.
There are many rational analyses that can be made on all these aspects, but they do not cut wood in the sense that the damaging behavior of established politicians, newsmedia, movement leaders is throttled down with their vocal rhetorics.
The simple messaging of EU bad, Brussels bad, the North selfish can be repeated at little effort.
The also simple messaging that integrating faster towards a Federation, with a United States of Europe, is the solution forward can be repeated also with little effort.
Both opinions do not need any serious evidence to be kept alive because utopias behind the horizon never need evidence.
And because we have not another "EU" in the world as comparison we cannot point to examples.
Considering the global changes and this diverging in the EU, Brexit a convenient experiment for the economical value of the EU Single Market membership.
What I seek is a way forward that does not contain much transformation risks but does deal with the main stings of the EU cohesion damage.
The Single Market stays as the biggest economical asset and biggest power tool.
Lots of "the great injustice" done to the South is argumentated with being chained into the Euro.
When all Eurozone member agree this can be changed quite easily.
But it would be a huge defeat for the Federalists.
=> When the Federalists prefer to continue the structural damaging taking place now above giving up their utopia.... so be it.
In that case they were either right in thinking they can weather out the storm.... or wrong in which case EU countries are going to vote with their feet.
Assuming the Federalists will give in one way or another... the South countries get the same choice they had in the early 90ies: "you can have the Euro when you comply to the fiscal and monetary discipline of the North"
With the lessons learned by now... that such a decision cannot be based on political makeability but must be founded in societal and economical realities... I can imagine some countries leave the Euro.
In this little step the Euro and ECB can still stay as they are only with a little bit less size and possibly less global clout.
It will anyway not affect the protection of traditional values and standards in the EU.
EDIT
Arakhor, perhaps better when my answer is moved to the EU thread
Sorry