With the UK out of the damned EU the rest of the world will be bigger economically and the EU represent a correspondingly smaller proportion. Without substantial reform, I know which I'd rather be part of.
As for terminology, I can think of far worse insults than 'remoaner', including a good number of unpleasant adjectives routinely levelled at the likes of Nigel Farage by some of the very same people who're now complaining about name calling. That's OK though because someone who believes in the independence of the the UK is fair game for any amount of abuse eh?...
It's a well known tactic of the left to employ the most appalling abuse, intimidation and worse in pursuit of their goals whilst at the same time playing victim whenever it suits. A good deal of that is going on right now in the context of the Brexit debate.