Ric
The educator in me says, "Get a degree". However, you could skip uni and get a quarter of your flying training done on the debt you would have had in the 3 years of studying.
There again, the student loan is the cheapest debt you're ever likely to get, and maybe you can't get the 15-20k upfront, so need traditional, expensive loans.
You'll need a good wage to save for the mod route, so perhaps we're back to the degree to maximise earnings. You could teach- 20k start, and 12 weeks to train in as you go along.
Don't go military unless it's your life's ambition. It won't work. Good luck.
CG
Leezy beat me to it, in part