1/ EU is arguably less corrupt (pro rata) than UK, USA, China, Russia, which is not to say that it's more efficient?
I'd put it at least 'marginally ahead' of UK/USA & well ahead of China/Russia. UK media has constantly bashed EU, for selfish reasons & infected many minds.
2/ Apart from OUR home mkt of EU27! UK has a growing Global Platform of EU trade deals (in which we have a say!) with 70+states eg S Korea, Canada, Japan. Our exporters ALREADY use that to good effect. Others eg NZ will do a deal with EU ahead of UK, coz of EU's scale.
3/ UK ALREADY sells £70billion to USA & £50billion to China EACH YEAR - without ANY FTA (free trade agreement). £120 billion of annual sales say it can be done NOW if we have the right product/price et al. There is NO barrier than leaving the EU removes!
4/ Many of the deals over which Brexiteers salivate (eg JRM & Fillet steak) relate to places like USA & Brazil dumping their cheap meat into the UK. I've not heard a single word about what products they're desperate to buy from UK that they can't already obtain?
6/ Anyone who thinks Brexit pain will be short-lived is seriously deluded. Even JRM has said it might take 50-75 YEARS to regain what we have NOW! Right now, HMG is borrowing loads more £££s to throw at its unplanned ferry-less Brexit. Our IMF 'ask' in 1976 comes to mind!
7/ UK has more than doubled Nat.debt since 2010! (to £2 trillion) GDP growth is already flat, and we're recession-bound NOW. With sterling falling & interest rates nudging up, ask your friends what level of yield investors will seek on UK Govt Bonds (say) 2-5 yrs from now?
10/ >50% x UK's trade is to EU27 & ex-EU's 70+ FTA's NOW. Putting that at risk to save c £9bn per annum of net EU membership is totally INSANE! as any numbers person will confirm. Of the tax we pay, circa 70p out of every £100 goes to EU membership. £99.30 is spent by HMG!