Make the European Union a sovereign state

Too many thing in one proposal. I can't agree on all of them. I suggest splitting them.

But we definitely need a proper government/parliament system that works democratically, and across countries

While I understand your idea and agree with it in principle I do not think there is enough support among the general population. There also would need to be a solid plan in place to ensure that smaller nations, such as Bulgaria and Belgium are not basically ruled by the larger states, such as Germany and France. Even at present there are legitimate concerns about larger forces (such as Germany and France) making decisions while ignoring or dismissing others. To be clear I agree that the EU should, at some point, should become a country or something resembling one. However, I disagree that that time is now as we have a lot of growing to do as a community, as opposed to individual countries. 

I actually disagree with your independence idea. A EU wide vote on someone's freedom should not be the case for one simple reason: what happens if said group votes to leave and most others decide they should stay? Do we send the troops in? The EU, our EU, should not force people to stay through military strength but through presenting clear benefits for participants, being transparent and clearly communicating and receiving feedback on actions and directions in the and of the union.

EU is in a deep crisis, thorn apart out of bad (to say less) bureaucratic governance, plus deep and fatal internal controversies. It's barely the time to think about the One Country idea, no matter how tempting it is. Too many radical opinions, dire economical situation (Greece, Italy, Brexit, etc.) heavy problems with the migrants and terrorism, etc., etc. 

What we can do, is to make a test. We can establish a Sovereign EU-Colony in the Atlantic, in International Waters, in a Tropical Zone somewhere between Portugal and Madeira, called EU 2.0 for example. This Colony will be built on multi-storey modular floating ship platforms, made of super-strong, lightweight, super-cheap and practically eternal Basalt-Fiber Composites. 

The Colony will be EU-Property and every EU-Member state will be able to participate in this project if it likes, with as much money as it likes.

The amount paid will determine the Votes this country will have in the Colony's Governance.

The Colony will be able to room 1-2 Million people for the beginning, but it could be upgraded with new modules without any limit of expansion. 

The Colony Model could be used for establishing a Floating Island for Migrants, based on the Australian model. This Island will be a full copy of EU, just at a remote territory. 

Colony will have a liberal (offshore) tax & duty and regulations regime, different to the existing EU law & regulation system, in order to attract people and companies to come live, work and doing business on the Colony.  "Zero-Waste" will be the main slogan of the Colony.

In a very short time, the Colony will become one of the best and nicest place in the world for business and entertainment. It'll be one of the world's biggest trade and technology center.

If this experiment succeed, it could be used as a governance model for spreading over the entire EU.

Otherwise, unfortunately, I don't have too many good hopes about it.

https://float-colony.alle.bg

That's a ... creative solution. I think it is not more realistic than an European constituion.

Leo Klinkers and Herbert Tombeur propose a Federal Europe, modeled over the American and Swiss constitutions, supplied with the things they feel work with the current EU setup.

If you have time and you like constitutional law, The European Federal Papers make for a quite interesting read: http://www.europeanfederalistpapers.eu/index.php/en/papers/separate-papers 

After that, go read their proposed constitution, a synergy of the American and Swiss constitutions, mixed with the current EU treaty basis....

This sounds like an admirable ideal, but we are very very far from making it possible, or even broadly popular.

We may be able to consider it again when we have solved a lot of other issues, like inequality across the Union, and found a common fiscal formula that everyone is happy with... and a lot more. When everything else is in place, a sovereign EU may be able to come about quite naturally, but I don't expect to see it in my lifetime (and I'm not about to pop off anytime soon), and trying to force it will produce a backlash.

I am opposed that the EU should be a sovereign state. There are too wide differences in nationalities, practices, standards and values. Current EU countries should remain sovereign beyond which no EU state should stand. The EU is committed to promoting the same policy on everything, but it is up to the EU to decide which policies they adopt and which are not. The EU should also be reluctant to impose EU taxes. The tax burden in the Netherlands, for example, is already quite high. EU taxes on Dutch people are even more loss-making, whereas there is no compensation for this.