You need to enjoy life as a young person. There's certain things you can enjoy when your young you may not enjoy when your older. However it's also important to have your CPL available asap. You never know when the window of opportunity will open in an airline. I opted for the mortgage first and to do my CPL later. My other school friends chose to do their CPL first. Unfortunately for me, when the window of opportunity opened in the airlines in OZ I had a mortgage and no CPL, my mates that had their CPL also had some quality hours and got into the airlines. Now they got an airline job and a mortgage. I got a mortgage but no airline job. I'm now pumping big money into my licence to buy quality hours at the expense of the mortgage. I advise you to do your CPL first. You also need to have variety in life though. Plan it so that you put a certain amount aside for flying but make sure you take an occasional break to do something different. Good luck whichever path you choose. I know it can be a tough one.