I'm still balancing, but Alpha 3 is ready to post, I'm just tweaking the interest rate to force the player into buying upgrades to make more money to pay off the debt. I have decreased the rate of failure just a bit so now it's more about grinding to pay off chunks of debt rather than worrying about the repo man.
This was the easiest way I could implement your suggestion, but I still need to balance the economy around it:
