Personally, I am not a huge fan of these currency, trading or political blocs. The WTO exists for trade and I would much prefer it to be the vehicle for trade, rather than groups of geographically close-knit countries.
Likewise, subject to the outcome of the negotiations, I imagine after a period of uncertainty and perhaps some turmoil it will be for the best. The timing may be unfortunate for some though.
The EU is a good way to reach that final, ideal state.
The EU seems to be pretty effective at preventing wars within Europe. That's a good enough pro to cancel out all the other cons on my list. But hey, it's been three generations since our last big war, we are probably overdue on a reminder of why fully-industrialized total war is not such a great idea.
I like the EU for what it offers me: a market where I can buy and sell things knowing that some minimum rules are being respected, an area which allows me, as a person the freedom that I think every human being has, to move and work wherever he wants (although this is currently limited to EU citizens), and lots of other advantages.
Peace is good collateral effect.
Have we had no wars in Europe since WW2 because of the EU, or because the generations before us were sick of war?
Also the EU didn't stop a war in the Balkans…
Last time I checked the Balkans were within Europe!
Look I voted to remain and I'm probably going to leave the UK as I don't want to live in the UK post Brexit.
That said there's as many crazy claims for the success of the EU as there were for the UK leaving.
As an institution the EU is very much out of touch with the needs of the common people, and you've only got to look at how they treated Greece as an example (and the whole stupid thing of moving MPs to Strasbourg once a month)
The UK was never really committed to the EU and yet it got special treatment time and time again. I say this as an EU outsider.
The "common people" usually want all upsides with no downsides. No one can deliver that, buy the populist politicians depend on it and promise people the moon (see "closed borders and common market"). Good luck with the Tories and IndyRef 2.