In terms of what kind of an offer Europe offers to the UK, in the event that it does vote to leave, I can also see that playing out both ways.
I certainly see the logic of the "everything will end up looking pretty much the same as now" argument, that we will get a trade deal that allows both sides to maintain the status quo. It is certainly in everyone's interests - in some ways - for that to happen. But I wouldnt dismiss the other argument, the "they wont want to let the UK be seen to get a good deal" one, either, because it has an equally compelling logic: Euroscepticism is on the rise across the continent and the EU is not about to feed it by showing people that they dont actually need Europe, that all the benefits can be achieved just as well outside as inside.
If that idea takes root the project will unravel pretty quickly. And though I am on balance in favour of Europe I know it is far from perfect, only just about good, even. I can admit that it is motivated by self preservation more than anything else, and is capable of biting off its nose to spite its face. So politicians may well end up facing down corporate lobbying from their own countries calling for a constructive arrangement with the UK, because the longer term good of the European projects is more important than the short term interests of growth in this quarter, or a few billion euros worth of trade here or there. They will see it as a longer term play, a case of a bit of pain now for more gain several years down the line.
I am always a bit wary of overestimating the UK's importance in Europe, but there is a part of me that has this nagging suspicion that if we do leave the whole thing WILL unravel, regardless of what the Eurocrats do to discourage it. Its not because the UK is necessary to make Europe feasible, at all. It is more like a dam that has a small crack in it, once water finds a way through it is just a matter of time before the whole thing crumbles, and if Holland or Spain - or Greece for that matter - had been the ones leaving, it would probably have created similar pressures. That was widely acknowledged when Greece was staring down the barrel of "Grexit" and is why, people say, politicians fought so hard to keep it in, despite the fact it was a basket case.
What would have been nice would have been for this whole thing to have been an opportunity for real reform of Europe to make it less dysfunctional, better at taking decisions, more transparent, more accountable, more democratic. But inevitably it hasnt panned out that way. It is notable that none of the demands Cameron made looked to address these fundamental issues, he didnt ask for reform to the actual structure of Europe to make it more democratic, he went instead for cosmetic stuff he thought he could get quickly, and which could be dressed up as substantial solutions to perceived problems, like these hoardes of immigrants that gobble up benefits (despite the fact that there is no evidence to suggest immigrants come over here to claim benefits in any significant numbers at all.) That is understandable because he didnt have time to negotiate real reform, and even if he did, it wouldnt excite any of his own voters, particularly.