France and Germany are looking at leaving the EU also, these two and the U.K. are the biggest and strongest members of the EU. The EU need two strong countries in the EU to continue to be a large power that can help defend our part of the world if ISIS were to make an attack or if the US were to start a war, as well as the money aspect also. So if the UK were to leave the EU would make an example out of us to stop France and Germany from leaving, Russia keeps trying to attack us, we wouldn't receive any help from them if we left (even if we begged) just as a deterrent.
The NHS will be in trouble. A health care service that has been voted the best in the world. A health care service that the right winged government (who wish to privatise our health) are taking money away from each year to convince people that it is not any good because they cannot afford to help people like they could five years ago. With this in trouble there will also be human rights and workers rights in trouble, who knows what will happen to it when we leave the EU, people are already being worked close to death.
For most companies it's beneficial to stay, for example, the North East of England possesses the best Nissan factory in Europe (possibly the world) it builds the Juke and all of the other top of the line Nissan cars, if we leave the EU these companies will loose a lot of money because trading will the the EU will not be as good as it currently is and the U.K. Nissan will no longer be given the top of the line cars to build.
The governor of the Bank of England is voting remain, as is Fiscal and other monetary companies, if the man who runs the country's money is voting remain then that tells you what the best option is (considering money controls the entire world).
Unity is the way the world is going, anyone who does not believe that is ignorant. We will have off-Earth colonies because of over-population and just general interest to expand our reach into the universe and the world will need to be completely unionised in order to accommodate all of these changes. It definitely won't be any time soon, but we will be unionised. I feel that the UK will always be remembered for leaving the EU if we decide to do that today and it will affect us in the future when we do have worldwide unionisation