I would be interested in what, beyond a single market, you think the EU is but ought not to be?
Lets ask a slightly different question. What form does an institution need to be to oversee a trading union? And what resources does it need? The largest is the WTO. With a budget of CHF 197m in 2015, of which the UK contributed CHF 7.5m. The EU budget is about CHF 550m
So why does it need to be this large to just run as a single market?
Payments for research, education, farmers - these are not "single market" activities. In fact the EU breaks it's expenditure down into 6 (really 7) areas:
Economic and social cohesion ~ 33%
Competitiveness for growth ~ 12%
Sustainable growth ~ 42%
Security ~ 2%
Global Europe ~ 6%
Admin ~ 6%
And Special < 1%
(yes I know over 100%, but rounded figures)
A lot of this spending sounds like political, and not a single market, financing. So is the EU engaged in more than just running a single market? Is it, in effect, operating as a government of Europe on many ways. So like National Parliament uses funding to distribute wealth, and create growth, is it doing the same on a European level? The answer is yes. There is talk (will it happen? I doubt it anytime soon) of EU Army. There are cries for "more integration". Integration is not needed for a single market. (Again - not saying it will happen, but there is a desire among several of those in charge)
And then there is the direct underwriting of governments by the ECB (in effect putting the tax payers on the hook for the government debt - a huge issue for German, and only allowed due to a fudge). And look at what it did to the legally elected government of Greece. And the issues created in Spain and Italy. Issues the UK avoided by devaluing.
So the EU is far more than a single market. It is a EU government, operating with (admittedly) one hand tied behind it's back. Being driven by the more powerful to their needs. IT doesn't have the full array of powers necessary to do the job properly, and to my mind, it needs to either gain those powers, become a full "Nation", or it should revert back to being a Single Market.
And as for what I think of the projects it undertakes - these can still happen - let the individual countries decide if they want to help their neighbours (In the same realm of "Foreign Aid"). Let countries devalue if necessary - to save themselves, and their people. You can have the single market, and not have the rest.
For me - I see no need to go beyond the European Council. In otherwords - head of state (or representatives) meet to discuss bi-laterial (or multi-lateral) agreements, which then member countries implement (or not). Each country free to do what it wants. No need for the Council of EU, European Parliament, Commission, Court of Justice (but can see a role for a way for the EU countries to have disputes heard, in a WTO like way), ECB and European Auditors.
So let me spin the question around. Do you really believe the EU is only a single market?