As for the ever closer union... ignoring the issue that the UK has negotiated many opt-outs. Most Brexiters seem to be vehemently opposed to closer union. But where is the rational argument explaining precisely why closer union is a bad idea? In my experience, that almost always seems to be missing from the discussion. It's clear from your post that you massively object to closer union. But why? What rational reason do you have for believing it to be a bad thing?
Ever closer union assumes the eventual creation of a nation state-you cannot get any closer than that. But moreover, the dissolution of a current nation state (in this case the United Kingdom).
If you are going to the British people, to pitch the idea that at some unspecified point in the future, the United Kingdom will be absorbed as part of a great European nation state, you will have to teach them to let go a list of deeply personal institutions, that many feel "safe" and trusting of, and that they would need to learn to know and love a list of new pan-european institutions such as:
National healthcare
National broadcasting
New tiers of government, and their geographical locations and the politicans themselves
An entirely new legal system (English common law couldn't possibly survive in a pan-European state.)
Replacement of current and adoption of new currency
By accepting ever closer union, your essentially asking the public to gradually cede the makeup of the very world they know around them-that they have grown up with and their parents have grown up with. It is completely unfiar, to accept that rationale without going to the public and asking the permission to accept it-oh wait...
So to answer your question, "why is ever closer union a bad idea?"-It is a bad idea because I am comfortable with my own surroundings and my own identity. I like the United Kingdom, for all its faults, its one of the most stable, safe and prosperous countries on Earth. Why would I want to change that? You say you have never heard why ever closer union is a bad idea, but I have yet to be convinced by a Remainer that ever closer union is a good idea.
Because Sovereignty is a wonderful thing, baby. I already called this out last month - just what are the benefits of letting the buffoons at Westminster (or their Civil Servants) decide everything?
It probably shows a wilful ignorance of how the EU works compared to the UK. Such things in the EU go through a long process of negotiation, because they have to get the support of all nations. Having seen how UK decisions are made at first hand, which sometimes are based on the "ideas" of one person, it's impossible for me to see this as better.
There are a number of curious things about this. First of all, its disheartening to see that your connection with someone who treasures sovereignty of their country to a form of ignorance. However, you could be correct, and if so, the referendum campaign was Remain's chance to educate us all once and for all about the workings of the EU-however it evidently failed to do so.
First of all, all countries have their "baffoons", and I'm sure the EU has their fair share of them too. The argument your making appears to be that either you cannot trust national parliaments and we should create pan-continental parliaments or you cannot trust the British parliament specifially and it therefore must be superseded by a higher governing body. Both asertions do not make sense at all.
What decisions specifcally, do you think will be better made inside the European Union than in our own Parliament? Remainers typically argue, enviromental and security matters cannot just be decided in London and must be delegated Europe-wide. This I agree with, to an extent. While our own Parliament has the power to tighten up enviromental policies, there are larger matters, relating to say automotive manufacturing's impact on the enviroment that could be better made on a Euro wide level. However, this doesn't intrinsically require the EU to make happen, only a band of national governments who engage in dialouge and co-operation on a specific subject for mutal self interest.
Secondly, You cannot possibly argue directly or indirectly elected MEPs or unelected officals, are better placed to make judgements about the internal affairs of the United Kingdom-especially when the EU in its decision makings, are often bound by previous French advantages, German clout and pressure from poorer European countries. You said yourself, EU negotiations are often long and complicated, and require being accpetable by all member states with their own eurosceptic tendencies. Just look at how complicated it will be to amend a part of an existing European treaty, as oppose to removing or amending a part of existing UK legislation. Various books, such as David Goodhart's Road to Somewhere, argue that the public are most comfortable when access to their institutions or the centres of decision makings are ares local as possible, such as in Town Halls or capital cities. The Brexit vote was part inspired by the lack of affinity the British people felt with EU governing and legal institutions. Remainers who often point out the bad parts of Westminster (yet stay quiet on various other less stable European national governments), seem to rather jump ship completely and use Brussels as a shield against Westminster, and yet seem to offer no suggestions as to how we can make British politics a more stable and productive entitiy in itself.