The 'each country will furnish the following contingent for service upon request' route is NATO-lite.

If they want integration, reduce the national militaries to a division or so apiece and institute an EU force using one language, force structure, etc. funded by a levy drawn from all members by whatever apportionment seems most apt.

Coupled with mandatory conscription, it could even be used as a cultural change tool shifting folks towards a common Euro identity even more so then at present.


Just a thought...