Considering PM Merkel's words on EU, I think it's clear that there are deep limitations toward how much competences (or political power, effectively, by political decisions) that can be moved up to the EU supernational level! In comparing with USA and its federation, we have a long way to go on several issues, such as dealing with a diversity of languages, getting all nations into the Eurozone, getting the universities into a composed European network and getting the European business network working more coherently and concerted while avoiding the fallacies of USA that (we in the) EU now are approaching more wisely, I think! Cheers!
Note: You can object to the above "several issues" all you want, but I want you to update on US American financial radicalism first and dump the Gandhism (because it's effete) in doing so. Also, we need to start looking good as a group!
Note2: Please, also note that several of these issues may require 50 to 200 years and that we may never see a USA-federation-style political organisation come into being (in our life-time)!