Good point JT!
The one benefit of doing an aviation degree, then working in aviation is you are keeping the degree current by working in the field. If you do a psych degree as a back up that's fine but in ten years time when you are over aviation and looking to get back into it your degree will be almost worthless.
As someone above said, education can be an end in itself and university life is a lot of fun, you make lots of new friends and have some great times. You will be slogging it out up north for a number of years, nothing wrong with taking a year or two extra to enjoy being young and responsibility free!
I'd personally recommend uni of some sort (aviation, commerce, arts, science etc. as long as it interests you) but it really doesn't matter. That is purely based on what I wanted to experience in life.