This is a commonly cited reason for voting in but where is the power/impetus to enact change going to come from?
Don't assume you'll be asked again. If you disapprove of the EU in its current form, the only way to vote is Leave. I don't think that voting Remain in the expectation or hope that reform will take place is a realistic option when it is a system that is incredibly resistant to reform. The European leaders are only just starting to pay attention now that it looks like there's a fair chance Leave will win.