How about the UK taking the lead on setting up a new Euro-club, 'EU2' with those outside of the Euro Zone or not in the EU at all, so say UK, Switzerland,Norway, Sweden, Denmark, Czech Republic, Hungary, Poland etc., all the free trade stuff but none of the rest of the red-tape. If we're really desperate for more mates to join our new club, then bring in all the odd-balls, Macedonia, Montenegro, Bosnia & Herzecovina, Moldova, Bulgaria, Croatia, Romania, Iceland, Liechtenstein, Albania, Andorra, San Marino, Armenia and hey the Vatican City!
Once any of the Eurozone members want to follow the UK's lead and swap members clubs, the rest will tumble like a pack of cards and we'll end up with a new EU2 with all the benefits and none of the disadvantages.
Good to have some competition.