Nah, EU is a bureaucratic nightmare. Its an union of small petty empires all pushing for advantage through central, restrictive bureaucracy. All of them too large to run efficiently in the first place.
Whats needed is a weak union, with almost no bureaucracy, running only basic things. Strong small local government dealing with everything on local level, small population with vested interest to keep local government in check and ability of people to vote on their feet and leave places if they are shitty run.

We already tried that, the confederate system was a huge failure. The Federal government is simply more efficient, and well run states would undoubtedly put restrictions on immigration....they may as well be different countries.

no it was never attempted. Not even close.
City states, not states as now, because each state with spread out territory is a mini empire. Efficiency of central governments is horrible, because bureaucracy grows to incredible size and then expands to meets demands of expanding bureaucracy.
You govern on a small scale to deal with problems on local level thus directly responsible to the voter and use modern transport and communication to keep economy on massive scale.
System more similar to old swiss confederacy, then modern empire democracy.
And btw, Confederate states of USA were confederacy in name only. By their constitution and de facto centralist government they were a federation.

It's more than 100 sentences

Plus he's Magneto, you can;t fucking kill Magneto!

Hard to do that if you don't have one.

Ever heard of the ol' rub and tug?