Hmm... I think the most important part of funding education in this manner is to link programs or schools (possibly even the college level) to the degree taxed. This would have the intrinsic effect for limiting the degree program to the employment base that will be able to utilize those jobs. The reciprocal funding should then be able to manage gradual changes in employment demand - and large demand shifts could be funded through government or corporate "scholarships" which would be in effect a future tax credit. You could also allow for traditional payment for those who wish to make it through school without future tax burdens (i.e. I had zero debt at the end of my degrees - a combination of scholarship and work).
As a more critical immediate reform for education funding/loans, I think there should be a loan cap based on some multiple of the average yearly income expected for that degree (and that multiple shouldn't necessarily be greater than one). I think it's borderline criminal to allow young kids to pursue a degree while simultaneously loaning them money that you know will be many times their expected annual income - and then making sure that there's no way out of that debt - not even bankruptcy.