The idea is nice but we've tried this, and it got us hellish levels of inequality (gilded age, etc.).

I do see what you're saying, for instance setting a maximum interest rate on payday loans caused lenders to shift to that maximum (even those which were below before), and having rules about what's part-time or full-time work does tend to solidify jobs around those points (get as much work out of them as you can without providing health insurance, etc.) but the alternative doesn't seem to work.