I'm in favour of leaving the EU at the moment, and I've set out some of my reasons for wanting to leave below. Hoping some Remainers would explain why they disagree with these:
Firstly, no one has presented anything like a suggestion to solving the various calamities which the EU is walking towards. No one knows how the Greek debt will resolve, no one knows how the migrant crisis will resolve and no one knows how hard the EU is gonna push for the fiscal and political union its leaders so desire. Extremist, left and right wing populist parties are on the rise and the whole eurozone is trapped in a stagflationary cycle. And as ever, the EU is crippled by inactivity - it took a year and a half before they even started talking to Turkey about stopping migrant flow, and the Germans have already cocked that up. Too many different people, with different cultures and different ideologies and different ideas of how they should be run, makes it virtually impossible for any meaningful solutions to be found, as evidenced by pretty much the entirety of the EU's existence.
Secondly, the people who run the EU are unilaterally pushing closer integration, in spite of the overwhelming popular opinion being against it. It's a perversion of democracy. No one really wants this closer union except a bunch of bureaucrats in Brussels/Strasbourg - and if you want an example of EU ludicrousness, how about the ridiculous waste of resources that is the transfer of EU headquarters from Brussels to Strasbourg and back every month?
Thirdly, our economy is fundamentally different to those on the continent. Our income is built primarily on our services sector and especially our financial services, whereas continental european economies are dominated by manufacturing. The economic policy that would best suit ourselves will never be the same as that which will best serve the continental countries, and given as they outnumber us we'll lose out. We're already seeing the start of this with the push for closer financial regulations, which will eventually cripple our services sector.
Fourthly, our contribution to the EU is going to go up sharply. Continental Europe is stuck in a stagflationary cycle, whilst our economy is doing rather well by comparison. As this trend continues - and it is definitely set to continue - it is inevitable that our contributions will go up sooner of later. Coupled with the similarly inevitable erosion of our rebate, and soon we'll be a second Germany; bankrolling the EU, or more accurately covering the costs of the poorer East European countries.
Fifthly, immigration. I don't have an especial problem with people coming into our country, but an abundance of cheap unskilled labour is punching through the wage floor and dragging everyone else's pay down with it. I welcome the introduction of a National Living Wage, but this will inevitably draw even more unskilled workers into the UK labour market, which will end up counteracting any positives that low-paid workers would have gleaned. Perhaps more worryingly, is that over the next 3-10 years (depending on which EU country they live in) the migrants who have entered over the past couple years will be entitled to EU passports, giving them unfettered access to Britain. Now whilst they obviously aren't all terrorists and criminals, they do pretty unanimously have incredibly backwards views on women, homosexuals and democracy, amongst other things. It would be frankly dangerous to allow these kind of people, with these kind of ideologies, a place in Britain.
I'll finish on a point which I think gets less credit than it's due; national identity. I don't feel European, and neither do most people. Certainly not in the way they do on the continent. We identify more with Americans, Australians or even some asian cultures than we do with the French or the Germans, we share more culture with them. We really don't have a shared identity with those who live on the continent. Which makes the whole desire to tether ourselves to them, especially when they're faltering so obviously, rather obvious.