I second the "I wish that X were Y..." if it's speaking about something that could not be true, such as Australia moving significantly closer to Europe in my lifetime.Normally, I would say I wish that X were true, so I could Y, so for your example, volver, I wish that Australia were closer to Europe, so I could go there more often. The second part of the sentence is a little awkward as you give it. We can change the sentence around a little, which would give If Australia were closer to Europe I would go there more often.
I think it's called Conditional; If something were..., I would x.'if Australia were closer to Europe, I would go there more often'
is this an example of the subjunctive tense used in English?