Buy European

my lacking English

Your English wasn't incorrect, it's that disagreed with what you wrote. You used it has become which is the tense you use for something completed (as in, it has finished), while I believe it is not completed and for that reason wrote is becoming which is the same verb but in a different tense (as in, it is happening). I'm no native speaker, so might not be the best explanation. Someone please correct me if I'm wrong.

I think in your last comment all forms are all correct, and the tense in which you the verb to vote has different nuance but i wouldn't think something of it in this particular case. If you use 'are voting for' you basically mean how people would vote if they would have to vote today (or this week) and you would use 'voted for' mainly if it is relevant that it is different then how people would vote today. (Will) vote for, is voting for, will be voting are basically interchangeable, unless I am missing the nuance myself. You explain it correctly yourself so I think you understand it but I made you doubt yourself. Sorry for that.

Are you sure about that?

There are many politicians who consider the EU as not fully formed. The changes don't happen very fast, but it is in my view still an ongoing proces. For example, which countries are part of it continues to change (England left and others joined, more will likely join later), the euro itself hasn't changed but the countries it is used in still changes (Bulgaria is expected to switch over to the Euro next year) and also what is and isn't in the Schengen area changes, even this year with Gibraltar joining.

Another example of how, according to some, the EU would be more finished is with a 'multi-tier membership options', in which some countries have a tighter bond to the EU and others have a looser (think of how Norway and Switzerland aren't in the EU, but they are not entirely outside of it either).

There is lot has already been decided, so maybe it is already 90% finished, but there still is an ongoing debate on what the EU should end up looking like.

Since brexit leaving the EU hasn't looked like a very attractive option but still there is a lot of discussion on whether the EU should be smaller (e.g. having borders controlled by each individual member-state) or bigger (e.g. having a single combined army). In other words, there is still room to decide on what topics the EU should be big and on which it should be small. That makes the EU as it is right now very different than the US for example, where most of the expansion and integration happened two to three centuries ago (around the civil war mainly I think, but I'm no expert on US history either).