Here's a suggestion to assist David Cameron in his EU referendum "negotiations". Why not propose a scheme to eject from the EU all those countries which cause trouble and also fall below a certain ranking in the economic freedom league table.
Below is a list of EU countries in descending order of their economic freedom ranking. For example the EU could eject all those below a rank of 65 - Rwanda. So France, Italy, Croatia, Slovenia and Greece get the elbow. Maybe a criterion of 65 is a little lax but it seems fair enough as a starting point.